73 results on '"Jonathan M. Graff"'
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2. Mouse strains to study cold-inducible beige progenitors and beige adipocyte formation and function
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Daniel C. Berry, Yuwei Jiang, and Jonathan M. Graff
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Science - Abstract
Beige adipocytes are formed in response to cold and thought to contribute to organismal energy homeostasis. Here, the authors study a range of conditional and inducible RFP-expressing Cre mouse strains and find that SMA-based lines are the most useful for mapping beige adipocyte progenitor cells.
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- 2016
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3. Independent Stem Cell Lineages Regulate Adipose Organogenesis and Adipose Homeostasis
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Yuwei Jiang, Daniel C. Berry, Wei Tang, and Jonathan M. Graff
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Biology (General) ,QH301-705.5 - Abstract
Adipose tissues have striking plasticity, highlighted by childhood and adult obesity. Using adipose lineage analyses, smooth muscle actin (SMA)-mural cell-fate mapping, and conditional PPARγ deletion to block adipocyte differentiation, we find two phases of adipocyte generation that emanate from two independent adipose progenitor compartments: developmental and adult. These two compartments are sequentially required for organ formation and maintenance. Although both developmental and adult progenitors are specified during the developmental period and express PPARγ, they have distinct microanatomical, functional, morphogenetic, and molecular profiles. Furthermore, the two compartments derive from different lineages; whereas adult adipose progenitors fate-map from an SMA+ mural lineage, developmental progenitors do not. Remarkably, the adult progenitor compartment appears to be specified earlier than the developmental cells and then enters the already developmentally formed adipose depots. Thus, two distinct cell compartments control adipose organ development and organ homeostasis, which may provide a discrete therapeutic target for childhood and adult obesity.
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- 2014
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4. Exercise-Induced Skeletal Muscle Adaptations Alter the Activity of Adipose Progenitor Cells.
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Daniel Zeve, Douglas P Millay, Jin Seo, and Jonathan M Graff
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Medicine ,Science - Abstract
Exercise decreases adiposity and improves metabolic health; however, the physiological and molecular underpinnings of these phenomena remain unknown. Here, we investigate the effect of endurance training on adipose progenitor lineage commitment. Using mice with genetically labeled adipose progenitors, we show that these cells react to exercise by decreasing their proliferation and differentiation potential. Analyses of mouse models that mimic the skeletal muscle adaptation to exercise indicate that muscle, in a non-autonomous manner, regulates adipose progenitor homeostasis, highlighting a role for muscle-derived secreted factors. These findings support a humoral link between skeletal muscle and adipose progenitors and indicate that manipulation of adipose stem cell function may help address obesity and diabetes.
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- 2016
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5. Circulating glucose levels inversely correlate with Drosophila larval feeding through insulin signaling and SLC5A11
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Jonathan M. Graff, W. Mike Henne, Rupali Ugrankar, Fatih Akdemir, and Pano Theodoropoulos
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0301 basic medicine ,medicine.medical_specialty ,animal structures ,media_common.quotation_subject ,Medicine (miscellaneous) ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,RNA interference ,Internal medicine ,Hemolymph ,medicine ,Ingestion ,Drosophila ,lcsh:QH301-705.5 ,media_common ,biology ,fungi ,Appetite ,biology.organism_classification ,Trehalose ,Insulin receptor ,030104 developmental biology ,Endocrinology ,chemistry ,lcsh:Biology (General) ,Taste aversion ,biology.protein ,General Agricultural and Biological Sciences ,030217 neurology & neurosurgery - Abstract
In mammals, blood glucose levels likely play a role in appetite regulation yet the mechanisms underlying this phenomenon remain opaque. Mechanisms can often be explored from Drosophila genetic approaches. To determine if circulating sugars might be involved in Drosophila feeding behaviors, we scored hemolymph glucose and trehalose, and food ingestion in larvae subjected to various diets, genetic mutations, or RNAi. We found that larvae with glucose elevations, hyperglycemia, have an aversion to feeding; however, trehalose levels do not track with feeding behavior. We further discovered that insulins and SLC5A11 may participate in glucose-regulated feeding. To see if food aversion might be an appropriate screening method for hyperglycemia candidates, we developed a food aversion screen to score larvae with abnormal feeding for glucose. We found that many feeding defective larvae have glucose elevations. These findings highlight intriguing roles for glucose in fly biology as a potential cue and regulator of appetite.
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- 2018
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6. An RGS-containing sorting nexin controls Drosophila lifespan.
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Jae Myoung Suh, Drew Stenesen, John M Peters, Akiko Inoue, Angela Cade, and Jonathan M Graff
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Medicine ,Science - Abstract
The pursuit of eternal youth has existed for centuries and recent data indicate that fat-storing tissues control lifespan. In a D. melanogaster fat body insertional mutagenic enhancer trap screen designed to isolate genes that control longevity, we identified a regulator of G protein signaling (RGS) domain containing sorting nexin, termed snazarus (sorting nexin lazarus, snz). Flies with insertions into the 5' UTR of snz live up to twice as long as controls. Transgenic expression of UAS-Snz from the snz Gal4 enhancer trap insertion, active in fat metabolic tissues, rescued lifespan extension. Further, the lifespan extension of snz mutants was independent of endosymbiont, e.g., Wolbachia, effects. Notably, old snz mutant flies remain active and fertile indicating that snz mutants have prolonged youthfulness, a goal of aging research. Since mammals have snz-related genes, it is possible that the functions of the snz family may be conserved to humans.
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- 2008
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7. SMAD3 Regulates Follicle-stimulating Hormone Synthesis by Pituitary Gonadotrope Cells in Vivo
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Daniel J. Bernard, Chu-Xia Deng, Jonathan M. Graff, Gauthier Schang, Ulrich Boehm, and Yining Li
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Male ,0301 basic medicine ,endocrine system ,medicine.medical_specialty ,Pituitary gland ,030209 endocrinology & metabolism ,Gonadotrophs ,Biology ,Gonadotropic cell ,Biochemistry ,FSHB ,Mice ,03 medical and health sciences ,Follicle-stimulating hormone ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Gene Regulation ,Smad3 Protein ,Spermatogenesis ,Molecular Biology ,Infertility, Male ,Smad4 Protein ,Mice, Knockout ,integumentary system ,Exons ,Cell Biology ,Antral follicle ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Forkhead box L2 ,Hormone receptor ,Female ,Follicle Stimulating Hormone ,Luteinizing hormone ,Infertility, Female ,hormones, hormone substitutes, and hormone antagonists - Abstract
Pituitary follicle-stimulating hormone (FSH) is an essential regulator of fertility in females and of quantitatively normal spermatogenesis in males. Pituitary-derived activins are thought to act as major stimulators of FSH synthesis by gonadotrope cells. In vitro, activins signal via SMAD3, SMAD4, and forkhead box L2 (FOXL2) to regulate transcription of the FSHβ subunit gene (Fshb). Consistent with this model, gonadotrope-specific Smad4 or Foxl2 knock-out mice have greatly reduced FSH and are subfertile. The role of SMAD3 in vivo is unresolved; however, residual FSH production in Smad4 conditional knock-out mice may derive from partial compensation by SMAD3 and its ability to bind DNA in the absence of SMAD4. To test this hypothesis and determine the role of SMAD3 in FSH biosynthesis, we generated mice lacking both the SMAD3 DNA binding domain and SMAD4 specifically in gonadotropes. Conditional knock-out females were hypogonadal, acyclic, and sterile and had thread-like uteri; their ovaries lacked antral follicles and corpora lutea. Knock-out males were fertile but had reduced testis weights and epididymal sperm counts. These phenotypes were consistent with those of Fshb knock-out mice. Indeed, pituitary Fshb mRNA levels were nearly undetectable in both male and female knock-outs. In contrast, gonadotropin-releasing hormone receptor mRNA levels were significantly elevated in knock-outs in both sexes. Interestingly, luteinizing hormone production was altered in a sex-specific fashion. Overall, our analyses demonstrate that SMAD3 is required for FSH synthesis in vivo.
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- 2017
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8. Cellular Aging Contributes to Failure of Cold-Induced Beige Adipocyte Formation in Old Mice and Humans
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Eric D. Berglund, Robert W. Arpke, Jonathan M. Graff, Daniel C. Berry, Michael Kyba, Elizabeth L. Close, Aki Uchida, Yuwei Jiang, and David W. Reading
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Male ,0301 basic medicine ,Senescence ,Aging ,medicine.medical_specialty ,Physiology ,p38 mitogen-activated protein kinases ,Adipose tissue ,White adipose tissue ,Biology ,p38 Mitogen-Activated Protein Kinases ,Mural cell ,03 medical and health sciences ,Internal medicine ,medicine ,Animals ,Humans ,Adipocytes, Beige ,Progenitor cell ,Molecular Biology ,Cellular Senescence ,Cyclin-Dependent Kinase Inhibitor p16 ,Stem Cells ,Cell Biology ,Beige Adipocytes ,Phenotype ,Actins ,Cell biology ,Cold Temperature ,Mice, Inbred C57BL ,Cell metabolism ,030104 developmental biology ,Endocrinology ,Cellular Aging ,Thermogenesis - Abstract
Cold temperatures induce progenitor cells within white adipose tissue to form beige adipocytes that burn energy and generate heat; this is a potential anti-diabesity therapy. However, the potential to form cold-induced beige adipocytes declines with age. This creates a clinical roadblock to potential therapeutic use in older individuals, who constitute a large percentage of the obesity epidemic. Here we show that aging murine and human beige progenitor cells display a cellular aging, senescence-like phenotype that accounts for their age-dependent failure. Activating the senescence pathway, either genetically or pharmacologically, in young beige progenitors induces premature cellular senescence and blocks their potential to form cold-induced beige adipocytes. Conversely, genetically or pharmacologically reversing cellular aging by targeting the p38/MAPK-p16Ink4a pathway in aged mouse or human beige progenitor cells rejuvenates cold-induced beiging. This in turn increases glucose sensitivity. Collectively, these data indicate that anti-aging or senescence modalities could be a strategy to induce beiging, thereby improving metabolic health in aging humans.
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- 2017
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9. Macrophage Smad3 Protects the Infarcted Heart, Stimulating Phagocytosis and Regulating Inflammation
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Bijun Chen, Shuaibo Huang, Nikolaos G. Frangogiannis, Anis Hanna, Yi Jin Wu, Jonathan M. Graff, Ya Su, and Adipong Brickshawana
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Male ,Physiology ,Phagocytosis ,medicine.medical_treatment ,Myocardial Infarction ,Inflammation ,Mice, Transgenic ,SMAD ,Article ,Mice ,Fibrosis ,medicine ,Macrophage ,Animals ,Myocytes, Cardiac ,Smad3 Protein ,Cells, Cultured ,Mice, Knockout ,business.industry ,Macrophages ,medicine.disease ,Cytokine ,Cancer research ,Female ,medicine.symptom ,Mothers against decapentaplegic ,Cardiology and Cardiovascular Medicine ,business ,Transforming growth factor - Abstract
Rationale: TGF (transforming growth factor)-β is critically involved in myocardial injury, repair, and fibrosis, activating both Smad (small mothers against decapentaplegic)-dependent and non-Smad pathways. The in vivo role of TGF-β signaling in regulation of macrophage function is poorly understood. We hypothesized that in the infarcted myocardium, activation of TGF-β/Smad signaling in macrophages may regulate repair and remodeling. Objective: To investigate the role of macrophage-specific TGF-β Smad3 signaling in a mouse model of myocardial infarction and to dissect the mechanisms mediating Smad-dependent modulation of macrophage function. Methods and Results: TGF-βs markedly activated Smad3 in macrophages, without affecting Smad-independent pathways. Phagocytosis rapidly and directly activated macrophage Smad3, in the absence of active TGF-β release. MyS3KO (myeloid cell–specific Smad3 knockout) mice had no baseline defects but exhibited increased late mortality and accentuated dilative postmyocardial infarction remodeling. Adverse outcome in infarcted MyS3KO mice was associated with perturbations in phagocytic activity, defective transition of macrophages to an anti-inflammatory phenotype, scar expansion, and accentuated apoptosis of border zone cardiomyocytes. In vitro, Smad3 null macrophages exhibited reduced expression of genes associated with eat-me signals, such as Mfge8 (milk fat globule-epidermal growth factor factor 8), and reduced capacity to produce the anti-inflammatory mediators IL (interleukin)-10 and TGF-β1, and the angiogenic growth factor VEGF (vascular endothelial growth factor). Mfge8 partly rescued the phagocytic defect of Smad3 null macrophages, without affecting inflammatory activity. Impaired anti-inflammatory actions of Smad3 null macrophages were associated with marked attenuation of phagocytosis-induced PPAR (peroxisome proliferator-activated receptor) expression. MyS3KO mice had no significant alterations in microvascular density and interstitial fibrosis in remodeling myocardial segments. Conclusions: We demonstrate that Smad3 critically regulates function of infarct macrophages, by mediating acquisition of a phagocytic phenotype and by contributing to anti-inflammatory transition. Smad3-dependent actions in macrophages protect the infarcted heart from adverse remodeling.
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- 2019
10. Protective Effects of Activated Myofibroblasts in the Pressure-Overloaded Myocardium Are Mediated Through Smad-Dependent Activation of a Matrix-Preserving Program
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Shuaibo Huang, Anis Hanna, Michele Cavalera, Ya Su, Jonathan M. Graff, Nikolaos G. Frangogiannis, Arti V. Shinde, Ilaria Russo, Simon J. Conway, and Bijun Chen
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0301 basic medicine ,Physiology ,Inflammation ,SMAD ,030204 cardiovascular system & hematology ,Matrix metalloproteinase ,Matrix (biology) ,Matrix Metalloproteinase Inhibitors ,Extracellular matrix ,Transforming Growth Factor beta1 ,03 medical and health sciences ,Mice ,Transforming Growth Factor beta2 ,0302 clinical medicine ,Transforming Growth Factor beta3 ,medicine ,Pressure ,Animals ,Smad3 Protein ,Myofibroblasts ,Mice, Knockout ,Extracellular Matrix Proteins ,Tissue Inhibitor of Metalloproteinase-1 ,Ventricular Remodeling ,Chemistry ,Stroke Volume ,Cell biology ,030104 developmental biology ,Matrix Metalloproteinase 8 ,Stress, Mechanical ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,Myofibroblast ,Cell Adhesion Molecules - Abstract
Rationale: The heart contains abundant interstitial and perivascular fibroblasts. Traditional views suggest that, under conditions of mechanical stress, cytokines, growth factors, and neurohumoral mediators stimulate fibroblast activation, inducing ECM (extracellular matrix) protein synthesis and promoting fibrosis and diastolic dysfunction. Members of the TGF (transforming growth factor)-β family are upregulated and activated in the remodeling myocardium and modulate phenotype and function of all myocardial cell types through activation of intracellular effector molecules, the Smads (small mothers against decapentaplegic), and through Smad-independent pathways. Objectives: To examine the role of fibroblast-specific TGF-β/Smad3 signaling in the remodeling pressure-overloaded myocardium. Methods and Results: We examined the effects of cell-specific Smad3 loss in activated periostin-expressing myofibroblasts using a mouse model of cardiac pressure overload, induced through transverse aortic constriction. Surprisingly, FS3KO (myofibroblast-specific Smad3 knockout) mice exhibited accelerated systolic dysfunction after pressure overload, evidenced by an early 40% reduction in ejection fraction after 7 days of transverse aortic constriction. Accelerated systolic dysfunction in pressure-overloaded FS3KO mice was associated with accentuated matrix degradation and generation of collagen-derived matrikines, accompanied by cardiomyocyte myofibrillar loss and apoptosis, and by enhanced macrophage-driven inflammation. In vitro, TGF-β1, TGF-β2, and TGF-β3 stimulated a Smad3-dependent matrix-preserving phenotype in cardiac fibroblasts, suppressing MMP (matrix metalloproteinase)-3 and MMP-8 synthesis and inducing TIMP (tissue inhibitor of metalloproteinases)-1. In vivo, administration of an MMP-8 inhibitor attenuated early systolic dysfunction in pressure-overloaded FS3KO mice, suggesting that the protective effects of activated cardiac myofibroblasts in the pressure-overloaded myocardium are, at least in part, because of suppression of MMPs and activation of a matrix-preserving program. MMP-8 stimulation induces a proinflammatory phenotype in isolated macrophages. Conclusions: In the pressure-overloaded myocardium, TGF-β/Smad3-activated cardiac fibroblasts play an important protective role, preserving the ECM network, suppressing macrophage-driven inflammation, and attenuating cardiomyocyte injury. The protective actions of the myofibroblasts are mediated, at least in part, through Smad-dependent suppression of matrix-degrading proteases.
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- 2019
11. Circulating glucose levels inversely correlate with
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Rupali, Ugrankar, Pano, Theodoropoulos, Fatih, Akdemir, W Mike, Henne, and Jonathan M, Graff
- Abstract
In mammals, blood glucose levels likely play a role in appetite regulation yet the mechanisms underlying this phenomenon remain opaque. Mechanisms can often be explored from
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- 2018
12. SMAD2 and p38 signaling pathways act in concert to determine XY primordial germ cell fate in mice
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Kurumi Fukuda, Yumiko Saga, Jonathan M. Graff, Michael Weinstein, and Quan Wu
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Male ,endocrine system ,medicine.medical_specialty ,Nodal Protein ,Somatic cell ,Blotting, Western ,Retinoic acid ,Nodal signaling ,Tretinoin ,Smad2 Protein ,Biology ,Real-Time Polymerase Chain Reaction ,Fibroblast growth factor ,Models, Biological ,p38 Mitogen-Activated Protein Kinases ,Mice ,chemistry.chemical_compound ,FGF9 ,Internal medicine ,Image Processing, Computer-Assisted ,medicine ,Animals ,Molecular Biology ,In Situ Hybridization ,DNA Primers ,Inhibin-beta Subunits ,Analysis of Variance ,Mice, Inbred ICR ,Microscopy, Confocal ,Reverse Transcriptase Polymerase Chain Reaction ,Gene Expression Regulation, Developmental ,Cell Differentiation ,Spermatozoa ,Cell biology ,Endocrinology ,Testis determining factor ,chemistry ,Signal transduction ,NODAL ,Signal Transduction ,Developmental Biology - Abstract
The sex of primordial germ cells (PGCs) is determined in developing gonads on the basis of cues from somatic cells. In XY gonads, sex-determining region Y (SRY) triggers fibroblast growth factor 9 (FGF9) expression in somatic cells. FGF signaling, together with downstream nodal/activin signaling, promotes male differentiation in XY germ cells by suppressing retinoic acid (RA)-dependent meiotic entry and inducing male-specific genes. However, the mechanism by which nodal/activin signaling regulates XY PGC fate is unknown. We uncovered the roles of SMAD2/3 and p38 MAPK, the putative downstream factors of nodal/activin signaling, in PGC sexual fate decision. We found that conditional deletion of Smad2, but not Smad3, from XY PGCs led to a loss of male-specific gene expression. Moreover, suppression of RA signaling did not rescue male-specific gene expression in Smad2-mutant testes, indicating that SMAD2 signaling promotes male differentiation in a RA-independent manner. By contrast, we found that p38 signaling has an important role in the suppression of RA signaling. The Smad2 deletion did not disrupt the p38 signaling pathway even though Nodal expression was significantly reduced, suggesting that p38 was not regulated by nodal signaling in XY PGCs. Additionally, the inhibition of p38 signaling in the Smad2-mutant testes severely impeded XY PGC differentiation and induced meiosis. In conclusion, we propose a model in which p38 and SMAD2 signaling coordinate to determine the sexual fate of XY PGCs.
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- 2015
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13. Estrogen receptor inhibition enhances cold-induced adipocyte beiging and glucose sensitivity
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Kfir Lapid, Jonathan M. Graff, Eric D. Berglund, and Ajin Lim
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medicine.medical_specialty ,Fulvestrant ,medicine.drug_class ,business.industry ,Cellular differentiation ,Antagonist ,Estrogen receptor ,Stimulation ,Carbohydrate metabolism ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Estrogen ,Internal medicine ,Adipocyte ,medicine ,business ,medicine.drug - Abstract
Low estrogen states, exemplified by postmenopausal women, are associated with increased adiposity and metabolic dysfunction. We recently reported a paradox, in which a conditional estrogen receptor-alpha (ERα) mutant mouse shows a hyper-metabolic phenotype with enhanced brown/beige cell formation (“browning/beiging”). These observations led us to consider that although systemic deficiency of estrogen or ERα in mice results in obesity and glucose intolerance at room-temperature, cold-exposure might induce enhanced browning/beiging and improve glucose metabolism. Remarkably, studying cold-exposure in mouse models of inhibited estrogen signaling - ERαKO mice, ovariectomy, and treatment with the ERα antagonist Fulvestrant - supported this notion. ERα/estrogen deficient mice demonstrated enhanced cold-induced beiging, reduced adiposity and increased glucose sensitivity. Fulvestrant was also effective in diet-induced obesity settings. Mechanistically, ERα inhibition sensitized cell-autonomous beige cell differentiation and stimulation, including β3-adrenoreceptor-dependent adipocyte beiging. Taken together, our findings highlight a therapeutic potential for obese/diabetic postmenopausal patients.
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- 2017
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14. Distinct cellular and molecular mechanisms for β3 adrenergic receptor-induced beige adipocyte formation
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Jonathan M. Graff, Daniel C. Berry, and Yuwei Jiang
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0301 basic medicine ,medicine.medical_specialty ,Mouse ,Brite ,QH301-705.5 ,Science ,Cellular differentiation ,cold exposure ,Adipose tissue ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Internal medicine ,medicine ,Animals ,Adipocytes, Beige ,SMA ,Biology (General) ,Receptor ,PRDM16 ,adipose ,General Immunology and Microbiology ,biology ,General Neuroscience ,Cell Differentiation ,Cell Biology ,General Medicine ,Cold Temperature ,Mice, Inbred C57BL ,Developmental Biology and Stem Cells ,030104 developmental biology ,Endocrinology ,Adipogenesis ,Receptors, Adrenergic, beta-3 ,biology.protein ,beige adipocytes ,Medicine ,Receptors, Adrenergic, beta-1 ,Stem cell ,ACTA2 ,Developmental biology ,Research Article ,beta adrenergic receptors - Abstract
Beige/brite adipocytes are induced within white adipose tissues (WAT) and, when activated, consume glucose and fatty acids to produce heat. Classically, two stimuli have been used to trigger a beiging response: cold temperatures and β3-adrenergic receptor (Adrb3) agonists. These two beiging triggers have been used interchangeably but whether these two stimuli may induce beiging differently at cellular and molecular levels remains unclear. Here, we found that cold-induced beige adipocyte formation requires Adrb1, not Adrb3, activation. Adrb1 activation stimulates WAT resident perivascular (Acta2+) cells to form cold-induced beige adipocytes. In contrast, Adrb3 activation stimulates mature white adipocytes to convert into beige adipocytes. Necessity tests, using mature adipocyte-specific Prdm16 deletion strategies, demonstrated that adipocytes are required and are predominant source to generate Adrb3-induced, but not cold-induced, beige adipocytes. Collectively, we identify that cold temperatures and Adrb3 agonists activate distinct cellular populations that express different β-adrenergic receptors to induce beige adipogenesis., eLife digest Excess accumulation of a type of fat called white fat is associated with obesity and metabolic problems. White fat cells store energy. White fat tissue also contains some beige fat cells, which burn fats and sugars to produce heat. Cold temperatures trigger the production and activity of beige fat cells, which allows the body to stay warm. People with obesity tend to have less beige fat and more white fat. This has led scientists to test whether treatments that increase the number of beige fat cells a person has could reduce fat mass and improve metabolism. To develop treatments that increase beige fat, scientists must first understand where it comes from and how cold and other factors stimulate its growth. Recent studies have shown that smooth muscle cells, which surround blood vessel walls, make cold-induced beige fat cells. A widely used drug that turns on the β3 adrenergic receptor, which is found in the cell membrane, also boosts the creation of beige fat cells. Yet, it was not clear exactly how cold or this drug triggers the production of beige fat. Now, Jiang et al. show that drugs that target β3 adrenergic receptors cause white fat cells in mice to change into beige fat cells. The experiments also showed that cold turns on a different receptor called the β1 adrenergic receptor on smooth muscle cells causing them to make beige fat cells. This shows that there is more than one source for beige fat cells in the body and that different strategies for increasing beige fat cell numbers do not work the same way. More studies are needed to learn whether beige fat cells produced after exposure to cold or drugs behave in the same way and have similar affects on metabolism. This could help scientists determine if one of these strategies could make a better treatment for obesity or other metabolic disorders.
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- 2017
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15. Author response: Distinct cellular and molecular mechanisms for β3 adrenergic receptor-induced beige adipocyte formation
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Jonathan M. Graff, Daniel C. Berry, and Yuwei Jiang
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0301 basic medicine ,03 medical and health sciences ,β3 adrenergic receptor ,030104 developmental biology ,0302 clinical medicine ,030209 endocrinology & metabolism ,Biology ,Beige Adipocytes ,Cell biology - Published
- 2017
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16. A PPARγ transcriptional cascade directs adipose progenitor cell-niche interaction and niche expansion
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A-Young Jo, Michael Kyba, Jonathan M. Graff, Yuwei Jiang, Robert W. Arpke, Wei Tang, and Daniel C. Berry
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Male ,Vascular Endothelial Growth Factor A ,0301 basic medicine ,medicine.medical_specialty ,Science ,Niche ,General Physics and Astronomy ,Adipose tissue ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Receptor, Platelet-Derived Growth Factor beta ,Mice ,03 medical and health sciences ,Internal medicine ,Adipocytes ,medicine ,Animals ,Compartment (development) ,Stem Cell Niche ,Progenitor cell ,Receptor ,Cell Proliferation ,Adipogenesis ,Multidisciplinary ,Cell growth ,Stem Cells ,General Chemistry ,Cell biology ,PPAR gamma ,Endothelial stem cell ,030104 developmental biology ,Endocrinology ,Adipose Tissue ,Female - Abstract
Adipose progenitor cells (APCs) reside in a vascular niche, located within the perivascular compartment of adipose tissue blood vessels. Yet, the signals and mechanisms that govern adipose vascular niche formation and APC niche interaction are unknown. Here we show that the assembly and maintenance of the adipose vascular niche is controlled by PPARγ acting within APCs. PPARγ triggers a molecular hierarchy that induces vascular sprouting, APC vessel niche affinity and APC vessel occupancy. Mechanistically, PPARγ transcriptionally activates PDGFRβ and VEGF. APC expression and activation of PDGFRβ promotes the recruitment and retention of APCs to the niche. Pharmacologically, targeting PDGFRβ disrupts APC niche contact thus blocking adipose tissue expansion. Moreover, enhanced APC expression of VEGF stimulates endothelial cell proliferation and expands the adipose niche. Consequently, APC niche communication and retention are boosted by VEGF thereby impairing adipogenesis. Our data indicate that APCs direct adipose tissue niche expansion via a PPARγ-initiated PDGFRβ and VEGF transcriptional axis., Adipocyte progenitor cells (APCs) are found tethered to adipose tissue blood vessel walls and can differentiate into adipocytes. Here the authors show that PPARγ controls angiogenesis by stimulating APC–blood vessel interaction and retention via a transcriptional network that includes PDGFRβ and VEGF.
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- 2017
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17. Form(ul)ation of adipocytes by lipids
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Jonathan M. Graff and Kfir Lapid
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0301 basic medicine ,Cell signaling ,Histology ,Adipose tissue ,030209 endocrinology & metabolism ,Review ,Energy homeostasis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Adipocyte ,Lipidomics ,Adipocytes ,Humans ,Obesity ,Stem Cells ,Data interpretation ,Lipid metabolism ,Cell Differentiation ,Cell Biology ,Metabolism ,Lipid Metabolism ,Lipids ,Cell biology ,030104 developmental biology ,chemistry ,Adipose Tissue ,Energy Metabolism - Abstract
Lipids have the potential to serve as bio-markers, which allow us to analyze and to identify cells under various experimental settings, and to serve as a clinical diagnostic tool. For example, diagnosis according to specific lipids that are associated with diabetes and obesity. The rapid development of mass-spectrometry techniques enables identification and profiling of multiple types of lipid species. Together, lipid profiling and data interpretation forge the new field of lipidomics. Lipidomics can be used to characterize physiologic and pathophysiological processes in adipocytes, since lipid metabolism is at the core of adipocyte physiology and energy homeostasis. A significant bulk of lipids are stored in adipocytes, which can be released and used to produce energy, used to build membranes, or used as signaling molecules that regulate metabolism. In this review, we discuss how exhaust of lipidomes can be used to study adipocyte differentiation, physiology and pathophysiology.
- Published
- 2017
18. Independent Stem Cell Lineages Regulate Adipose Organogenesis and Adipose Homeostasis
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Daniel C. Berry, Yuwei Jiang, Wei Tang, and Jonathan M. Graff
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Aging ,Time Factors ,Organogenesis ,Adipose tissue ,Peroxisome proliferator-activated receptor ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Mice ,chemistry.chemical_compound ,Adipocyte ,Animals ,Homeostasis ,Compartment (development) ,Cell Lineage ,Progenitor cell ,lcsh:QH301-705.5 ,Progenitor ,chemistry.chemical_classification ,Staining and Labeling ,Stem Cells ,Cell biology ,PPAR gamma ,lcsh:Biology (General) ,Adipose Tissue ,chemistry ,Immunology ,Stem cell - Abstract
SummaryAdipose tissues have striking plasticity, highlighted by childhood and adult obesity. Using adipose lineage analyses, smooth muscle actin (SMA)-mural cell-fate mapping, and conditional PPARγ deletion to block adipocyte differentiation, we find two phases of adipocyte generation that emanate from two independent adipose progenitor compartments: developmental and adult. These two compartments are sequentially required for organ formation and maintenance. Although both developmental and adult progenitors are specified during the developmental period and express PPARγ, they have distinct microanatomical, functional, morphogenetic, and molecular profiles. Furthermore, the two compartments derive from different lineages; whereas adult adipose progenitors fate-map from an SMA+ mural lineage, developmental progenitors do not. Remarkably, the adult progenitor compartment appears to be specified earlier than the developmental cells and then enters the already developmentally formed adipose depots. Thus, two distinct cell compartments control adipose organ development and organ homeostasis, which may provide a discrete therapeutic target for childhood and adult obesity.
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- 2014
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19. Follicle‐stimulating hormone synthesis and fertility are intact in mice lacking SMAD3 DNA binding activity and SMAD2 in gonadotrope cells
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Jérôme Fortin, Daniel J. Bernard, Ulrich Boehm, Jonathan M. Graff, and Michael Weinstein
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Male ,endocrine system ,Transcription, Genetic ,Ovariectomy ,Smad2 Protein ,SMAD ,Biology ,Gonadotropic cell ,Polymerase Chain Reaction ,Biochemistry ,FSHB ,Research Communications ,Mice ,Follicle-stimulating hormone ,Transcription (biology) ,Testis ,Genetics ,Animals ,Sexual Maturation ,Smad3 Protein ,Spermatogenesis ,Molecular Biology ,Mice, Knockout ,integumentary system ,DNA ,Molecular biology ,Mice, Inbred C57BL ,Fertility ,Cell culture ,Pituitary Gland ,Knockout mouse ,Female ,Follicle Stimulating Hormone ,biological phenomena, cell phenomena, and immunity ,Protein Binding ,Biotechnology - Abstract
The activin/inhibin system regulates follicle-stimulating hormone (FSH) synthesis and release by pituitary gonadotrope cells in mammals. In vitro cell line data suggest that activins stimulate FSH β-subunit (Fshb) transcription via complexes containing the receptor-regulated SMAD proteins SMAD2 and SMAD3. Here, we used a Cre-loxP approach to determine the necessity for SMAD2 and/or SMAD3 in FSH synthesis in vivo. Surprisingly, mice with conditional mutations in both Smad2 and Smad3 specifically in gonadotrope cells are fertile and produce FSH at quantitatively normal levels. Notably, however, we discovered that the recombined Smad3 allele produces a transcript that encodes the entirety of the SMAD3 C-terminal Mad homology 2 (MH2) domain. This protein behaves similarly to full-length SMAD3 in Fshb transcriptional assays. As the truncated protein lacks the N-terminal Mad homology 1 (MH1) domain, these results show that SMAD3 DNA-binding activity as well as SMAD2 are dispensable for normal FSH synthesis in vivo. Furthermore, the observation that deletion of proximal exons does not remove all SMAD3 function may facilitate interpretation of divergent phenotypes previously described in different Smad3 knockout mouse lines.—Fortin, J., Boehm, U., Weinstein, M. B., Graff, J. M., Bernard, D. J. Follicle-stimulating hormone synthesis and fertility are intact in mice lacking SMAD3 DNA binding activity and SMAD2 in gonadotrope cells.
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- 2013
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20. The developmental origins of adipose tissue
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Jonathan M. Graff, Drew Stenesen, Daniel Zeve, and Daniel C. Berry
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medicine.medical_specialty ,Cellular differentiation ,Reviews ,Adipose tissue ,Biology ,chemistry.chemical_compound ,Internal medicine ,Adipocyte ,Adipocytes ,medicine ,Animals ,Humans ,Stem Cell Niche ,Molecular Biology ,Stem Cells ,Cell Differentiation ,Cell biology ,Endocrinology ,Adipose Tissue ,chemistry ,Vascular niche ,Stem cell ,Stem cell biology ,Developmental biology ,Homeostasis ,Developmental Biology - Abstract
Adipose tissue is formed at stereotypic times and locations in a diverse array of organisms. Once formed, the tissue is dynamic, responding to homeostatic and external cues and capable of a 15-fold expansion. The formation and maintenance of adipose tissue is essential to many biological processes and when perturbed leads to significant diseases. Despite this basic and clinical significance, understanding of the developmental biology of adipose tissue has languished. In this Review, we highlight recent efforts to unveil adipose developmental cues, adipose stem cell biology and the regulators of adipose tissue homeostasis and dynamism.
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- 2013
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21. FGFR2IIIb-MAPK Activity Is Required for Epithelial Cell Fate Decision in the Lower Müllerian Duct
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Altea Rocchi, Vanida A. Serna, Jonathan M. Graff, Jumpei Terakawa, Takeshi Kurita, and Erwin P. Bottinger
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0301 basic medicine ,medicine.medical_specialty ,Fibroblast Growth Factor 7 ,Pyridines ,Mesenchyme ,Cellular differentiation ,Fluorescent Antibody Technique ,Smad2 Protein ,Cell fate determination ,Biology ,Bone morphogenetic protein ,Real-Time Polymerase Chain Reaction ,03 medical and health sciences ,Paracrine signalling ,Mice ,Endocrinology ,Internal medicine ,medicine ,Animals ,Benzodioxoles ,Smad3 Protein ,Receptor, Fibroblast Growth Factor, Type 2 ,Molecular Biology ,Mullerian Ducts ,Original Research ,Mice, Knockout ,FGF10 ,Uterus ,Imidazoles ,Cell Differentiation ,Epithelial Cells ,General Medicine ,Epithelium ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,Bone morphogenetic protein 4 ,Animals, Newborn ,embryonic structures ,Core Binding Factor Alpha 2 Subunit ,Vagina ,Female ,Mitogen-Activated Protein Kinases ,Fibroblast Growth Factor 10 - Abstract
Cell fate of lower Mullerian duct epithelium (MDE), to become uterine or vaginal epithelium, is determined by the absence or presence of ΔNp63 expression, respectively. Previously, we showed that SMAD4 and runt-related transcription factor 1 (RUNX1) were independently required for MDE to express ΔNp63. Here, we report that vaginal mesenchyme directs vaginal epithelial cell fate in MDE through paracrine activation of fibroblast growth factor (FGF) receptor-MAPK pathway. In the developing reproductive tract, FGF7 and FGF10 were enriched in vaginal mesenchyme, whereas FGF receptor 2IIIb was expressed in epithelia of both the uterus and vagina. When Fgfr2 was inactivated, vaginal MDE underwent uterine cell fate, and this differentiation defect was corrected by activation of MEK-ERK pathway. In vitro, FGF10 in combination with bone morphogenetic protein 4 and activin A (ActA) was sufficient to induce ΔNp63 in MDE, and ActA was essential for induction of RUNX1 through SMAD-independent pathways. Accordingly, inhibition of type 1 receptors for activin in neonatal mice induced uterine differentiation in vaginal epithelium by down-regulating RUNX1, whereas conditional deletion of Smad2 and Smad3 had no effect on vaginal epithelial differentiation. In conclusion, vaginal epithelial cell fate in MDE is induced by FGF7/10-MAPK, bone morphogenetic protein 4-SMAD, and ActA-RUNX1 pathway activities, and the disruption in any one of these pathways results in conversion from vaginal to uterine epithelial cell fate.
- Published
- 2016
22. Exercise-Induced Skeletal Muscle Adaptations Alter the Activity of Adipose Progenitor Cells
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Douglas P. Millay, Jonathan M. Graff, Jin Seo, and Daniel Zeve
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0301 basic medicine ,Male ,Cellular differentiation ,lcsh:Medicine ,Adipose tissue ,Biochemistry ,Fats ,Mice ,Animal Cells ,Adipocytes ,Medicine and Health Sciences ,Morphogenesis ,Homeostasis ,lcsh:Science ,Musculoskeletal System ,Connective Tissue Cells ,Oligonucleotide Array Sequence Analysis ,Multidisciplinary ,Muscles ,Stem Cells ,Cell Differentiation ,Muscle Differentiation ,Lipids ,Adaptation, Physiological ,medicine.anatomical_structure ,Adipose Tissue ,Connective Tissue ,Stem cell ,Cellular Types ,Anatomy ,Research Article ,medicine.medical_specialty ,Adipose tissue macrophages ,Green Fluorescent Proteins ,Skeletal muscle adaptation ,Mice, Transgenic ,Biology ,Real-Time Polymerase Chain Reaction ,Cell Line ,03 medical and health sciences ,Internal medicine ,3T3-L1 Cells ,Physical Conditioning, Animal ,medicine ,Adipocyte Differentiation ,Diabetes Mellitus ,Animals ,Cell Lineage ,Obesity ,Progenitor cell ,Muscle, Skeletal ,Progenitor ,Cell Proliferation ,lcsh:R ,Skeletal muscle ,Biology and Life Sciences ,Cell Biology ,Glucose Tolerance Test ,030104 developmental biology ,Endocrinology ,Biological Tissue ,Skeletal Muscles ,Culture Media, Conditioned ,Physical Endurance ,lcsh:Q ,Thrombospondins ,Developmental Biology - Abstract
Exercise decreases adiposity and improves metabolic health; however, the physiological and molecular underpinnings of these phenomena remain unknown. Here, we investigate the effect of endurance training on adipose progenitor lineage commitment. Using mice with genetically labeled adipose progenitors, we show that these cells react to exercise by decreasing their proliferation and differentiation potential. Analyses of mouse models that mimic the skeletal muscle adaptation to exercise indicate that muscle, in a non-autonomous manner, regulates adipose progenitor homeostasis, highlighting a role for muscle-derived secreted factors. These findings support a humoral link between skeletal muscle and adipose progenitors and indicate that manipulation of adipose stem cell function may help address obesity and diabetes.
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- 2016
23. Emerging Roles of Adipose Progenitor Cells in Tissue Development, Homeostasis, Expansion and Thermogenesis
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Jonathan M. Graff, Daniel C. Berry, and Yuwei Jiang
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0301 basic medicine ,Endocrinology, Diabetes and Metabolism ,Regeneration (biology) ,Stem Cells ,Adipose tissue ,Thermogenesis ,White adipose tissue ,Biology ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Endocrinology ,Adipose Tissue ,Immunology ,Animals ,Homeostasis ,Humans ,Progenitor cell ,Stem cell ,Progenitor - Abstract
Stem or progenitor cells are an essential component for the development, homeostasis, expansion, and regeneration of many tissues. Within white adipose tissue (WAT) reside vascular-resident adipose progenitor cells (APCs) that can proliferate and differentiate into either white or beige/brite adipocytes, which may control adiposity. Recent studies have begun to show that APCs can be manipulated to control adiposity and counteract 'diabesity'. However, much remains unknown about the identity of APCs and how they may control adiposity in response to homeostatic and external cues. Here, we discuss recent advances in our understanding of adipose progenitors and cover a range of topics, including the stem cell/progenitor lineage, their niche, their developmental and adult roles, and their role in cold-induced beige/brite adipocyte formation.
- Published
- 2016
24. Mouse strains to study cold-inducible beige progenitors and beige adipocyte formation and function
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Jonathan M. Graff, Daniel C. Berry, and Yuwei Jiang
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0301 basic medicine ,Science ,General Physics and Astronomy ,Mice, Inbred Strains ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Mural cell ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Inbred strain ,Fate mapping ,Adipocyte ,Adipocytes ,Animals ,Progenitor cell ,Muscle, Skeletal ,Cells, Cultured ,Regulation of gene expression ,Genetics ,Multidisciplinary ,Gene Expression Regulation, Developmental ,General Chemistry ,Beige Adipocytes ,Cell biology ,Cold Temperature ,030104 developmental biology ,chemistry ,Blood Vessels ,Function (biology) - Abstract
Cold temperatures induce formation of beige adipocytes, which convert glucose and fatty acids to heat, and may increase energy expenditure, reduce adiposity and lower blood glucose. This therapeutic potential is unrealized, hindered by a dearth of genetic tools to fate map, track and manipulate beige progenitors and ‘beiging'. Here we examined 12 Cre/inducible Cre mouse strains that mark adipocyte, muscle and mural lineages, three proposed beige origins. Among these mouse strains, only those that marked perivascular mural cells tracked the cold-induced beige lineage. Two SMA-based strains, SMA-CreERT2 and SMA-rtTA, fate mapped into the majority of cold-induced beige adipocytes and SMA-marked progenitors appeared essential for beiging. Disruption of the potential of the SMA-tracked progenitors to form beige adipocytes was accompanied by an inability to maintain body temperature and by hyperglycaemia. Thus, SMA-engineered mice may be useful to track and manipulate beige progenitors, beige adipocyte formation and function., Beige adipocytes are formed in response to cold and thought to contribute to organismal energy homeostasis. Here, the authors study a range of conditional and inducible RFP-expressing Cre mouse strains and find that SMA-based lines are the most useful for mapping beige adipocyte progenitor cells.
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- 2016
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25. Osteoclast Progenitors Reside in the Peroxisome Proliferator-Activated Receptor γ-Expressing Bone Marrow Cell Population
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Jonathan M. Graff, Wei Wei, Daniel Zeve, Wei Tang, Yang Du, Yihong Wan, Paul C. Dechow, and Xueqian Wang
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Male ,Transcription, Genetic ,Cellular differentiation ,Gene Expression ,Osteoclasts ,Peroxisome proliferator-activated receptor ,Mice ,Genes, Reporter ,Receptor, Notch1 ,Cells, Cultured ,chemistry.chemical_classification ,education.field_of_study ,biology ,Stem Cells ,Cell Differentiation ,Articles ,Organ Size ,Cell biology ,GATA2 Transcription Factor ,Isoenzymes ,medicine.anatomical_structure ,RANKL ,Female ,Stem cell ,Proto-Oncogene Proteins c-fos ,musculoskeletal diseases ,Recombinant Fusion Proteins ,Acid Phosphatase ,Green Fluorescent Proteins ,Osteocalcin ,Population ,Bone Marrow Cells ,Mice, Transgenic ,Collagen Type I ,Osteoclast ,Genetic model ,medicine ,Animals ,Cell Lineage ,education ,Molecular Biology ,Tibia ,Tartrate-Resistant Acid Phosphatase ,Gene Expression Profiling ,Cell Biology ,Antigens, Differentiation ,Molecular biology ,Peptide Fragments ,PPAR gamma ,Radiography ,chemistry ,biology.protein ,Bone marrow - Abstract
Osteoclasts are bone-resorbing cells essential for skeletal development, homeostasis, and regeneration. They derive from hematopoietic progenitors in the monocyte/macrophage lineage and differentiate in response to RANKL. However, the precise nature of osteoclast progenitors is a longstanding and important question. Using inducible peroxisome proliferator-activated receptor γ (PPARγ)-tTA TRE-GFP (green fluorescent protein) reporter mice, we show that osteoclast progenitors reside specifically in the PPARγ-expressing hematopoietic bone marrow population and identify the quiescent PPARγ(+) cells as osteoclast progenitors. Importantly, two PPARγ-tTA TRE-Cre-controlled genetic models provide compelling functional evidence. First, Notch activation in PPARγ(+) cells causes high bone mass due to impaired osteoclast precursor proliferation. Second, selective ablation of PPARγ(+) cells by diphtheria toxin also causes high bone mass due to decreased osteoclast numbers. Furthermore, PPARγ(+) cells respond to both pathological and pharmacological resorption-enhancing stimuli. Mechanistically, PPARγ promotes osteoclast progenitors by activating GATA2 transcription. These findings not only identify the long-sought-after osteoclast progenitors but also establish unprecedented tools for their visualization, isolation, characterization, and genetic manipulation.
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- 2011
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26. Thiazolidinediones Regulate Adipose Lineage Dynamics
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Wei Tang, Daniel Zeve, A-Young Jo, Jonathan M. Graff, and Jin Seo
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medicine.medical_specialty ,medicine.drug_class ,Physiology ,Adipose Tissue, White ,Adipose tissue macrophages ,Cellular differentiation ,Adipose tissue ,White adipose tissue ,Biology ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Adipocytes ,medicine ,Animals ,Cell Lineage ,Thiazolidinedione ,Molecular Biology ,Cell Proliferation ,030304 developmental biology ,0303 health sciences ,Stem Cells ,Cell Differentiation ,Cell Biology ,3. Good health ,Cell biology ,Endocrinology ,Adipogenesis ,Thiazolidinediones ,Stem cell ,Rosiglitazone ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Summary White adipose tissue regulates metabolism; the importance of this control is highlighted by the ongoing pandemic of obesity and associated complications such as diabetes, atherosclerosis, and cancer. White adipose tissue maintenance is a dynamic process, yet very little is known about how pharmacologic stimuli affect such plasticity. Combining in vivo lineage marking and BrdU labeling strategies, we found that rosiglitazone, a member of the thiazolidinedione class of glucose-lowering medicines, markedly increases the evolution of adipose progenitors into adipocytes. Notably, chronic rosiglitazone administration disrupts the adipogenic and self-renewal capacities of the stem cell compartment and alters its molecular characteristics. These data unravel unknown aspects of adipose dynamics and provide a basis to manipulate the adipose lineage for therapeutic ends.
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- 2011
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27. Search for transmembrane protein in gastric cancer by the Escherichia coli ampicillin secretion trap: expression of DSC2 in gastric cancer with intestinal phenotype
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Naohide Oue, Masazumi Okajima, Naoya Sakamoto, Jonathan M. Graff, Tetsutaro Hayashi, Wataru Yasui, Kazuhiro Sentani, Tsuyoshi Noguchi, Katsuhiro Anami, and Takao Hinoi
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Male ,Candidate gene ,Biology ,Pathology and Forensic Medicine ,Stomach Neoplasms ,Tumor Cells, Cultured ,medicine ,Humans ,CDX2 Transcription Factor ,Neoplasm Invasiveness ,Secretion ,CDX2 ,Gene ,Aged ,Cell Proliferation ,Gene Library ,Desmocollins ,Homeodomain Proteins ,Genetics ,Reverse Transcriptase Polymerase Chain Reaction ,Gene Expression Profiling ,Cancer ,Middle Aged ,medicine.disease ,Phenotype ,Molecular biology ,Transmembrane protein ,Neoplasm Proteins ,Gene Expression Regulation, Neoplastic ,Female ,Desmocollin - Abstract
Gastric cancer (GC) is one of the most common malignancies worldwide. Genes expressed only in cancer tissue, and especially on the cell membrane, will be useful molecular markers for diagnosis and may also be good therapeutic targets. To identify genes that encode transmembrane proteins present in GC, we generated Escherichia coli ampicillin secretion trap (CAST) libraries from two GC cell lines and normal stomach. By sequencing 4320 colonies from CAST libraries, we identified 30 candidate genes that encode transmembrane proteins present in GC. Quantitative reverse transcription-polymerase chain reaction analysis of these candidates revealed that ZDHHC14, BST2, DRAM2, and DSC2 were expressed much more highly in GC than in 14 kinds of normal tissues. Among these, DSC2 encodes desmocollin 2, which is one of three known desmocollins. Immunohistochemical analysis demonstrated that 22 (28%) of 80 GC cases were positive for desmocollin 2, and desmocollin 2 expression was observed frequently in GC with the intestinal mucin phenotype. Furthermore, desmocollin 2 expression was correlated with CDX2 expression. These results suggest that expression of desmocollin 2, induced by CDX2, may be a key regulator for GC with the intestinal mucin phenotype. Our results provide a list of genes that have high potential as a diagnostic and therapeutic target for GC. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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- 2010
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28. Atf4 Regulates Obesity, Glucose Homeostasis, and Energy Expenditure
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Elizabeth J. Parks, Christopher M. Adams, Edgardo S. Fortuno, Jae Myoung Suh, Tim M. Townes, Wei Tang, Jin Seo, Drew Stenesen, and Jonathan M. Graff
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medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Mutant ,Green Fluorescent Proteins ,Adipose tissue ,Mice, Transgenic ,Carbohydrate metabolism ,Activating Transcription Factor 4 ,Biology ,Mice ,Insulin resistance ,Genes, Reporter ,Internal medicine ,Gene expression ,Internal Medicine ,medicine ,Cyclic AMP ,Diabetes Mellitus ,Glucose homeostasis ,Animals ,Homeostasis ,Obesity ,Amino Acids ,Conserved Sequence ,Mice, Knockout ,Gene Expression Profiling ,Fatty Acids ,medicine.disease ,Phenotype ,Hypoglycemia ,Mice, Mutant Strains ,Endocrinology ,Drosophila melanogaster ,Glucose ,Larva ,Mutation ,Original Article ,Energy Metabolism ,Obesity Studies - Abstract
OBJECTIVE We evaluate a potential role of activating transcription factor 4 (Atf4) in invertebrate and mammalian metabolism. RESEARCH DESIGN AND METHODS With two parallel approaches—a fat body–specific green fluorescent protein enhancer trap screen in D. melanogaster and expression profiling of developing murine fat tissues—we identified Atf4 as expressed in invertebrate and vertebrate metabolic tissues. We assessed the functional relevance of the evolutionarily conserved expression by analyzing Atf4 mutant flies and Atf4 mutant mice for possible metabolic phenotypes. RESULTS Flies with insertions at the Atf4 locus have reduced fat content, increased starvation sensitivity, and lower levels of circulating carbohydrate. Atf4 null mice are also lean, and they resist age-related and diet-induced obesity. Atf4 null mice have increased energy expenditure potentially accounting for the lean phenotype. Atf4 null mice are hypoglycemic, even before substantial changes in fat content, indicating that Atf4 regulates mammalian carbohydrate metabolism. In addition, the Atf4 mutation blunts diet-induced diabetes as well as hyperlipidemia and hepatosteatosis. Several aspects of the Atf4 mutant phenotype resemble mice with mutations in components of the target of rapamycin (TOR) pathway. Consistent with the phenotypic similarities, Atf4 null mice have reduced expression of genes that regulate intracellular amino acid concentrations and lower intracellular concentration of amino acids, a key TOR input. Further, Atf4 mutants have reduced S6K activity in liver and adipose tissues. CONCLUSIONS Atf4 regulates age-related and diet-induced obesity as well as glucose homeostasis in mammals and has conserved metabolic functions in flies.
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- 2009
29. Redundant Roles of SMAD2 and SMAD3 in Ovarian Granulosa Cells In Vivo
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Jonathan M. Graff, Martin M. Matzuk, Qinglei Li, Carolina J. Jorgez, Stephanie A. Pangas, and Michael Weinstein
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Ovulation ,endocrine system ,medicine.medical_specialty ,media_common.quotation_subject ,Granulosa cell ,Ovary ,Smad2 Protein ,Biology ,Growth differentiation factor-9 ,Mice ,Internal medicine ,Conditional gene knockout ,Follicular phase ,medicine ,Animals ,Smad3 Protein ,Molecular Biology ,media_common ,Mice, Knockout ,Cumulus Cells ,Granulosa Cells ,Cell growth ,General Medicine ,Articles ,Cell Biology ,Transforming growth factor beta ,Cell biology ,medicine.anatomical_structure ,Endocrinology ,Reproductive Medicine ,biology.protein ,Female ,biological phenomena, cell phenomena, and immunity ,NODAL ,Infertility, Female - Abstract
Transforming growth factor beta (TGF-beta) superfamily members are critical in maintaining cell growth and differentiation in the ovary. Although signaling of activins, TGF-betas, growth differentiation factor 9, and nodal converge preferentially to SMAD2 and SMAD3, the in vivo functions and redundancy of these SMADs in the ovary and female reproduction remain largely unidentified. To circumvent the deleterious phenotypic aspects of ubiquitous deletion of Smad2 and Smad3, a conditional knockout strategy was formulated to selectively inactivate Smad2, Smad3, or both Smad2 and Smad3 in ovarian granulosa cells. While granulosa cell ablation of individual Smad2 or Smad3 caused insignificant changes in female fertility, deletion of both Smad2 and Smad3 led to dramatically reduced female fertility and fecundity. These defects were associated with the disruption of multiple ovarian processes, including follicular development, ovulation, and cumulus cell expansion. Furthermore, the impaired expansion of cumulus cells may be partially associated with altered cumulus expansion-related transcripts that are regulated by SMAD2/3 signaling. Our results indicate that SMAD2 and SMAD3 function redundantly in vivo to maintain normal female fertility and further support the involvement of an intraovarian SMAD2/3 pathway in mediating oocyte-produced signals essential for coordinating key events of the ovulatory process.
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- 2008
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30. Tripeptidyl peptidase II promotes fat formation in a conserved fashion
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Jae Myoung Suh, Renée M. McKay, James P. McKay, Jonathan M. Graff, and Leon Avery
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Heterozygote ,medicine.medical_treatment ,Scientific Report ,Mutant ,Aminopeptidases ,Biochemistry ,Mice ,RNA interference ,3T3-L1 Cells ,Genetics ,medicine ,Animals ,Caenorhabditis elegans ,Caenorhabditis elegans Proteins ,Dipeptidyl-Peptidases and Tripeptidyl-Peptidases ,Receptor ,Molecular Biology ,Adipogenesis ,Protease ,biology ,Serine Endopeptidases ,Tripeptidyl peptidase II ,Lipid Metabolism ,biology.organism_classification ,Peptide Fragments ,Adipose Tissue ,Mutation ,Daf-2 ,RNA Interference ,Receptors, Cholecystokinin ,Cholecystokinin - Abstract
Tripeptidyl peptidase II (TPPII) is a multifunctional and evolutionarily conserved protease. In the mammalian hypothalamus, TPPII has a proposed anti-satiety role affected by degradation of the satiety hormone cholecystokinin 8. Here, we show that TPPII also regulates the metabolic homoeostasis of Caenorhabditis elegans; TPPII RNA interference (RNAi) decreases worm fat stores. However, this occurs independently of feeding behaviour and seems to be a function within fat-storing tissues. In mammalian cell culture, TPPII stimulates adipogenesis and TPPII RNAi blocks adipogenesis. The pro-adipogenic action of TPPII seems to be independent of protease function, as catalytically inactive TPPII also increases adipogenesis. Mice that were homozygous for an insertion in the Tpp2 locus were embryonic lethal. However, Tpp2 heterozygous mutants were lean compared with wild-type littermates, although food intake was normal. These findings indicate that TPPII has central and peripheral roles in regulating metabolism and that TPPII actions in fat-storing tissues might be an ancient function carried out in a protease-independent manner.
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- 2007
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31. SMAD3 Regulates Gonadal Tumorigenesis
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Qinglei Li, Jonathan M. Graff, Anne E O'Connor, Kate L Loveland, and Martin M. Matzuk
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Male ,endocrine system ,medicine.medical_specialty ,Ovary ,SMAD ,Biology ,medicine.disease_cause ,Cachexia ,Mice ,Follicle-stimulating hormone ,Endocrinology ,Testicular Neoplasms ,Internal medicine ,Weight Loss ,medicine ,Animals ,Inhibins ,RNA, Messenger ,Smad3 Protein ,Wasting Syndrome ,Molecular Biology ,Pathological ,Mice, Knockout ,Ovarian Neoplasms ,General Medicine ,medicine.disease ,Penetrance ,Activins ,Cell Transformation, Neoplastic ,medicine.anatomical_structure ,Female ,Follicle Stimulating Hormone ,Carcinogenesis ,hormones, hormone substitutes, and hormone antagonists - Abstract
Inhibin is a secreted tumor suppressor and an activin antagonist. Inhibin alpha null mice develop gonadal sex cord-stromal tumors with 100% penetrance and die of a cachexia-like syndrome due to increased activin signaling. Because Sma and Mad-related protein (SMAD)2 and SMAD3 transduce activin signals in vitro, we attempted to define the role of SMAD3 in gonadal tumorigenesis and the wasting syndrome by generating inhibin alpha and Smad3 double mutant mice. Inhibin alpha and Smad3 double homozygous males were protected from early tumorigenesis and the usual weight loss and death. Approximately 90% of these males survived to 26 wk in contrast to 95% of inhibin-deficient males, which develop bilateral testicular tumors and die of the wasting syndrome by 12 wk. Testicular tumors were either absent or unilaterally slow growing and less hemorrhagic in the majority of double-knockout males. In contrast, development of the ovarian tumors and wasting syndrome was delayed, but still occurred, in the majority of the double-knockout females by 26 wk. In double mutant females, tumor development was accompanied by typical activin-induced pathological changes. In summary, we identify an important function of SMAD3 in gonadal tumorigenesis in both sexes. However, this effect is significantly more pronounced in the male, indicating that SMAD3 is the primary transducer of male gonadal tumorigenesis, whereas SMAD3 potentially overlaps with SMAD2 function in the ovary. Moreover, the activin-induced cachexia syndrome is potentially mediated through both SMAD2 and SMAD3 or only through SMAD2 in the liver and stomach. These studies identify sexually dimorphic functions of SMAD3 in gonadal tumorigenesis.
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- 2007
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32. Hedgehog signaling plays a conserved role in inhibiting fat formation
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Jae Myoung Suh, Xiaohuan Gao, Jonathan M. Graff, Zack Salo, Renée M. McKay, and James P. McKay
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medicine.medical_specialty ,Physiology ,Fat Body ,Peroxisome proliferator-activated receptor ,Adipose tissue ,DEVBIO ,Biology ,GATA Transcription Factors ,Evolution, Molecular ,Mice ,Osteogenesis ,3T3-L1 Cells ,Internal medicine ,medicine ,Animals ,Drosophila Proteins ,Hedgehog Proteins ,Obesity ,Molecular Biology ,Transcription factor ,Hedgehog ,Conserved Sequence ,chemistry.chemical_classification ,Mice, Inbred C3H ,Adipogenesis ,Multipotent Stem Cells ,Cell Biology ,Hedgehog signaling pathway ,Cell biology ,PPAR gamma ,Disease Models, Animal ,Drosophila melanogaster ,Endocrinology ,Adipose Tissue ,chemistry ,NIH 3T3 Cells ,GATA transcription factor ,Signal transduction ,Biomarkers ,Signal Transduction - Abstract
SummaryHedgehog (Hh) signals regulate invertebrate and vertebrate development, yet the role of the cascade in adipose development was undefined. To analyze a potential function, we turned to Drosophila and mammalian models. Fat-body-specific transgenic activation of Hh signaling inhibits fly fat formation. Conversely, fat-body-specific Hh blockade stimulated fly fat formation. In mammalian models, sufficiency and necessity tests showed that Hh signaling also inhibits mammalian adipogenesis. Hh signals elicit this function early in adipogenesis, upstream of PPARγ, potentially diverting preadipocytes as well as multipotent mesenchymal prescursors away from adipogenesis and toward osteogenesis. Hh may elicit these effects by inducing the expression of antiadipogenic transcription factors such as Gata2. These data support the notion that Hh signaling plays a conserved role, from invertebrates to vertebrates, in inhibiting fat formation and highlighting the potential of the Hh pathway as a therapeutic target for osteoporosis, lipodystrophy, diabetes, and obesity.
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- 2006
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33. Selective Identification of Secreted and Transmembrane Breast Cancer Markers using Escherichia coli Ampicillin Secretion Trap
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Matthew R. Muenster, Jeoffrey J. Schageman, Harold R. Garner, Richard B. Gaynor, John O. Schorge, Jonathan M. Graff, Carlos Becerra, J. Warren Huff, Qun S. Zang, Noelle S. Williams, Yun Lian, Deborah A. Ferguson, Raheela Ashfaq, Jeffrey A. Spencer, and Alexander Pertsemlidis
- Subjects
Signal peptide ,Cancer Research ,Breast Neoplasms ,Protein Sorting Signals ,Biology ,beta-Lactamases ,Breast cancer ,Plasmid ,Amp resistance ,Complementary DNA ,Biomarkers, Tumor ,Escherichia coli ,medicine ,Humans ,Secretion ,Ovarian Neoplasms ,Genetics ,Reverse Transcriptase Polymerase Chain Reaction ,cDNA library ,Gene Expression Profiling ,Reproducibility of Results ,Cancer ,medicine.disease ,Molecular biology ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,Oncology ,Female ,Ampicillin Resistance ,Gene Deletion ,Plasmids - Abstract
Secreted and cell surface proteins play important roles in cancer and are potential drug targets and tumor markers. Here, we describe a large-scale analysis of the genes encoding secreted and cell surface proteins in breast cancer. To identify these genes, we developed a novel signal sequence trap method called Escherichia coli ampicillin secretion trap (CAST). For CAST, we constructed a plasmid in which the signal sequence of β-lactamase was deleted such that it does not confer ampicillin resistance. Eukaryotic cDNA libraries cloned into pCAST produced tens of thousands of ampicillin-resistant clones, 80% of which contained cDNA fragments encoding secreted and membrane spanning proteins. We identified 2,708 unique sequences from cDNA libraries made from surgical breast cancer specimens. We analyzed the expression of 1,287 of the 2,708 genes and found that 166 were overexpressed in breast cancers relative to normal breast tissues. Eighty-five percent of these genes had not been previously identified as markers of breast cancer. Twenty-three of the 166 genes (14%) were relatively tissue restricted, suggesting use as cancer-specific targets. We also identified several new markers of ovarian cancer. Our results indicate that CAST is a robust, rapid, and low cost method to identify cell surface and secreted proteins and is applicable to a variety of relevant biological questions.
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- 2005
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34. C. elegans
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Jonathan M. Graff, Leon Avery, Renée M. McKay, and James P. McKay
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Genetics ,biology ,ved/biology ,ved/biology.organism_classification_rank.species ,Helminth genetics ,Cell Biology ,biology.organism_classification ,Phenotype ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,Mitochondrial respiratory chain ,chemistry ,Adipocyte ,Model organism ,Molecular Biology ,Transcription factor ,Caenorhabditis elegans ,Developmental Biology ,Genetic screen - Abstract
To gain insights into the genetic cascades that regulate fat biology, we evaluated C. elegans as an appropriate model organism. We generated worms that lack two transcription factors, SREBP and C/EBP, crucial for formation of mammalian fat. Worms deficient in either of these genes displayed a lipid-depleted phenotype-pale, skinny, larval-arrested worms that lack fat stores. On the basis of this phenotype, we used a reverse genetic screen to identify several additional genes that play a role in worm lipid storage. Two of the genes encode components of the mitochondrial respiratory chain (MRC). When the MRC was inhibited chemically in worms or in a mammalian adipocyte model, fat accumulation was markedly reduced. A third encodes lpd-3, whose homolog is also required for fat storage in a mammalian model. These data suggest that C. elegans is a genetically tractable model to study the mechanisms that underlie the biology of fat-storing tissues.
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- 2003
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35. Smad10 Is Required for Formation of the Frog Nervous System
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Jonathan M. Graff, Renée M. McKay, Edgardo S. Fortuno, and James A. LeSueur
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Nervous system ,medicine.medical_specialty ,Embryo, Nonmammalian ,Xenopus ,Bone morphogenetic protein 8A ,Smad Proteins ,MAP Kinase Kinase Kinase 3 ,Smad2 Protein ,SMAD ,In Vitro Techniques ,Xenopus Proteins ,Biology ,Kidney ,Fibroblast growth factor ,Bone morphogenetic protein ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Morphogenesis ,medicine ,Animals ,Nerve Growth Factors ,Phosphorylation ,Molecular Biology ,Smad4 Protein ,030304 developmental biology ,Embryonic Induction ,0303 health sciences ,Proteins ,Heart ,Cell Biology ,MAP Kinase Kinase Kinases ,Cell biology ,DNA-Binding Proteins ,Bone morphogenetic protein 6 ,Bone morphogenetic protein 5 ,Endocrinology ,medicine.anatomical_structure ,Trans-Activators ,Carrier Proteins ,Neural development ,030217 neurology & neurosurgery ,Signal Transduction ,Transcription Factors ,Developmental Biology - Abstract
Before the nervous system establishes its complex array of cell types and connections, multipotent cells are instructed to adopt a neural fate and an anterior-posterior pattern is established. In this report, we show that Smad10, a member of the Smad family of intracellular transducers of TGFβ signaling, is required for formation of the nervous system. In addition, two types of molecules proposed as key to neural induction and patterning, bone morphogenetic protein (BMP) antagonists and fibroblast growth factor (FGF), require Smad10 for these activities. These data suggest that Smad10 may be a central mediator of the development of the frog nervous system.
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- 2002
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36. Oestrogen signalling in white adipose progenitor cells inhibits differentiation into brown adipose and smooth muscle cells
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Kfir Lapid, Deborah J. Clegg, Jonathan M. Graff, Ajin Lim, and Daniel Zeve
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Male ,medicine.medical_specialty ,Adipose Tissue, White ,Cellular differentiation ,Green Fluorescent Proteins ,Myocytes, Smooth Muscle ,Neovascularization, Physiologic ,General Physics and Astronomy ,Adipose tissue ,Cell Separation ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Mice ,Random Allocation ,Adipose Tissue, Brown ,Transforming Growth Factor beta ,Internal medicine ,medicine ,Animals ,Myocyte ,Cell Lineage ,Progenitor cell ,Cell Proliferation ,Progenitor ,Multidisciplinary ,Stem Cells ,Estrogen Receptor alpha ,Cell Differentiation ,Estrogens ,General Chemistry ,Flow Cytometry ,Mice, Mutant Strains ,Phenotype ,Endocrinology ,Adipose Tissue ,Adipogenesis ,Mutation ,Female ,Stem cell ,Estrogen receptor alpha ,Signal Transduction - Abstract
Oestrogen, often via oestrogen receptor alpha (ERα) signalling, regulates metabolic physiology, highlighted by post-menopausal temperature dysregulation (hot flashes), glucose intolerance, increased appetite and reduced metabolic rate. Here we show that ERα signalling has a role in adipose lineage specification in mice. ERα regulates adipose progenitor identity and potency, promoting white adipogenic lineage commitment. White adipose progenitors lacking ERα reprogramme and enter into smooth muscle and brown adipogenic fates. Mechanistic studies highlight a TGFβ programme involved in progenitor reprogramming downstream of ERα signalling. The observed reprogramming has profound metabolic outcomes; both female and male adipose-lineage ERα-mutant mice are lean, have improved glucose sensitivity and are resistant to weight gain on a high-fat diet. Further, they are hypermetabolic, hyperphagic and hyperthermic, all consistent with a brown phenotype. Together, these findings indicate that ERα cell autonomously regulates adipose lineage commitment, brown fat and smooth muscle cell formation, and systemic metabolism, in a manner relevant to prevalent metabolic diseases.
- Published
- 2014
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37. Drosophila glucome screening identifies Ck1alpha as a regulator of mammalian glucose metabolism
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Benjamin L. Ebert, Rupali Ugrankar, Jungsik Noh, Rebekka K. Schneider, Christopher Tran, Jonathan M. Graff, Min Kim, Fatih Akdemir, and Eric D. Berglund
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Male ,Fat Body ,Regulator ,General Physics and Astronomy ,Adipose tissue ,Receptors, Cytoplasmic and Nuclear ,Carbohydrate metabolism ,medicine.disease_cause ,General Biochemistry, Genetics and Molecular Biology ,Article ,Mice ,Hemolymph ,medicine ,Animals ,Protein kinase A ,Drosophila ,Transcription factor ,Genetics ,Mutation ,Multidisciplinary ,biology ,Casein Kinase I ,Muscles ,fungi ,Trehalose ,General Chemistry ,biology.organism_classification ,3. Good health ,Drosophila melanogaster ,Glucose ,Adipose Tissue ,Hyperglycemia ,Metabolome ,Carbohydrate Metabolism ,Female ,Gene-Environment Interaction ,Transcription Factors - Abstract
Circulating carbohydrates are an essential energy source, perturbations in which are pathognomonic of various diseases, diabetes being the most prevalent. Yet many of the genes underlying diabetes and its characteristic hyperglycaemia remain elusive. Here we use physiological and genetic interrogations in D. melanogaster to uncover the ‘glucome', the complete set of genes involved in glucose regulation in flies. Partial genomic screens of ∼1,000 genes yield ∼160 hyperglycaemia ‘flyabetes' candidates that we classify using fat body- and muscle-specific knockdown and biochemical assays. The results highlight the minor glucose fraction as a physiological indicator of metabolism in Drosophila. The hits uncovered in our screen may have conserved functions in mammalian glucose homeostasis, as heterozygous and homozygous mutants of Ck1alpha in the murine adipose lineage, develop diabetes. Our findings demonstrate that glucose has a role in fly biology and that genetic screenings carried out in flies may increase our understanding of mammalian pathophysiology., Diabetes is associated with aberrations in glucose metabolism. Here the authors perform a genomic screen in fruit flies to identify new regulators of fly glucose metabolism, and show that mice lacking the murine homologue of one of their hits, the protein kinase CK1alpha, in the adipose lineage develop diabetes.
- Published
- 2014
38. The Casein Kinase I Family in Wnt Signaling
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Renée M. McKay, John M. Peters, and Jonathan M. Graff
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Dishevelled Proteins ,Dishevelled ,Casein Kinase I ,Protein Isoforms ,Phosphorylation ,Cells, Cultured ,beta Catenin ,chemistry.chemical_classification ,0303 health sciences ,Reverse Transcriptase Polymerase Chain Reaction ,030302 biochemistry & molecular biology ,Wnt signaling pathway ,LRP6 ,LRP5 ,Cell Differentiation ,Phenotype ,Multigene Family ,Casein kinase 1 ,Signal transduction ,Casein Kinases ,Signal Transduction ,Blotting, Western ,Biology ,03 medical and health sciences ,Wnt ,Proto-Oncogene Proteins ,Two-Hybrid System Techniques ,Animals ,Humans ,Caenorhabditis elegans ,Molecular Biology ,030304 developmental biology ,Adaptor Proteins, Signal Transducing ,Cell Biology ,Zebrafish Proteins ,Phosphoproteins ,beta-Galactosidase ,Protein Structure, Tertiary ,Wnt Proteins ,Cytoskeletal Proteins ,chemistry ,Mutation ,Cancer research ,Oocytes ,Trans-Activators ,RNA ,Cattle ,Protein Kinases ,Gene Deletion ,Developmental Biology - Abstract
The canonical Wnt-signaling pathway is critical for many aspects of development, and mutations in components of the Wnt pathway are carcinogenic. Recently, sufficiency tests identified casein kinase Iepsilon (CKIepsilon) as a positive component of the canonical Wnt/beta-catenin pathway, and necessity tests showed that CKIepsilon is required in vertebrates to transduce Wnt signals. In addition to CKIepsilon, the CKI family includes several other isoforms (alpha, beta, gamma, and delta) and their role in Wnt sufficiency tests had not yet been clarified. However, in Caenorhabditis elegans studies, loss-of-function of a CKI isoform most similar to alpha produced the mom phenotype, indicative of loss-of-Wnt signaling. In this report, we examine the ability of the various CKI isoforms to activate Wnt signaling and find that all the wild-type CKI isoforms do so. Dishevelled (Dsh), another positive component of the Wnt pathway, becomes phosphorylated in response to Wnt signals. All the CKI isoforms, with the exception of gamma, increase the phosphorylation of Dsh in vivo. In addition, CKI directly phosphorylates Dsh in vitro. Finally, we find that CKI is required in vivo for the Wnt-dependent phosphorylation of Dsh. These studies advance our understanding of the mechanism of Wnt action and suggest that more than one CKI isoform is capable of transducing Wnt signals in vivo.
- Published
- 2001
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39. Spemann organizer activity of Smad10
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Jonathan M. Graff and James A. LeSueur
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Dorsum ,Mesoderm ,Embryo, Nonmammalian ,animal structures ,Molecular Sequence Data ,Gene Dosage ,Smad Proteins ,Bone Morphogenetic Protein 4 ,Xenopus Proteins ,Biology ,Neural tissues ,Nervous System ,Xenopus laevis ,medicine ,Animals ,Amino Acid Sequence ,Nerve Growth Factors ,Cloning, Molecular ,Molecular Biology ,Embryonic Induction ,Genetics ,Sequence Homology, Amino Acid ,Gene Expression Regulation, Developmental ,Proteins ,Cell biology ,medicine.anatomical_structure ,Bone Morphogenetic Proteins ,embryonic structures ,Intercellular Signaling Peptides and Proteins ,Functional activity ,Signal transduction ,Spemann Organizer ,Neural development ,Signal Transduction ,Developmental Biology - Abstract
The Spemann organizer induces neural tissue, dorsalizes mesoderm and generates a second dorsal axis. We report the isolation and characterization of Smad10, which has all three of these Spemann activities. Smad10 is expressed at the appropriate time to transduce Spemann signals endogenously. Like the organizer, Smad10 generates anterior and posterior neural tissues. Smad10 appears to function downstream of the Spemann organizer, consistent with a role in mediating organizer-derived signals. Interestingly, Smad10, unlike previously characterized mediators of Spemann activity, does not appear to block BMP signals. This finding, coupled with the functional activity and expression profile, suggests that Smad10 mediates Spemann action in a novel manner.
- Published
- 1999
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40. Mechanisms of MARCKS Gene Activation during XenopusDevelopment
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Elizabeth A. Kennington, Yi Shi, Diana M. Pitterle, Perry J. Blackshear, Stephen K. Sullivan, and Jonathan M. Graff
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Transcriptional Activation ,DNA, Complementary ,animal structures ,Sp1 Transcription Factor ,Molecular Sequence Data ,Xenopus ,Regulatory Sequences, Nucleic Acid ,Biology ,Biochemistry ,Cell Line ,Mice ,Xenopus laevis ,Transcription (biology) ,Transcriptional regulation ,Animals ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,MARCKS ,Myristoylated Alanine-Rich C Kinase Substrate ,Promoter Regions, Genetic ,Molecular Biology ,Protein kinase C ,Cell Nucleus ,Reporter gene ,Binding Sites ,Base Sequence ,Sequence Homology, Amino Acid ,Intracellular Signaling Peptides and Proteins ,Gene Expression Regulation, Developmental ,Membrane Proteins ,Proteins ,Promoter ,Cell Biology ,biology.organism_classification ,Molecular biology ,MARCKS Gene ,Transcription Factors - Abstract
The myristoylated alanine-rich protein kinase C substrate (MARCKS) is a high affinity cellular substrate for protein kinase C. The MARCKS gene is under multiple modes of transcriptional control, including cytokine- and transformation-dependent, cell-specific, and developmental regulation. This study evaluated the transcriptional control of MARCKS gene expression during early development of Xenopus laevis. Xenopus MARCKS was highly conserved with its mammalian and avian homologues; its mRNA and protein were abundant in the maternal pool and increased after the mid-blastula transition (MBT). The Xenopus MARCKS gene was similar to those of other species, except that a second intron interrupted the 5'- untranslated region. By transiently transfecting XTC-2 cells and microinjecting Xenopus embryos with reporter gene constructs containing serial deletions of 5'-flanking MARCKS sequences, we identified a 124-base pair minimal promoter that was critical for promoter activity. Developmental gel shift assays revealed that a CBF/NF-Y/CP-1-like factor and an Sp1-like factor bound to this region in a manner correlating with the onset of Xenopus MARCKS transcription at MBT. Mutations in the promoter that abolished binding of these two factors also completely inhibited transcriptional activation of the MARCKS gene at MBT. The binding sites for these two factors are highly conserved in the human and mouse MARCKS promoters, suggesting that these elements might also regulate MARCKS transcription in other species. These studies not only increase our knowledge of the transcriptional regulation of the MARCKS genes but also have implications for the mechanisms responsible for zygotic activation of the Xenopus genome at MBT.
- Published
- 1997
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41. Embryonic Patterning: To BMP or Not to BMP, That Is the Question
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Jonathan M. Graff
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Genetics ,Mesoderm ,Biochemistry, Genetics and Molecular Biology(all) ,Wnt signaling pathway ,Ectoderm ,Germ layer ,Biology ,Embryonic stem cell ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,medicine.anatomical_structure ,Bone Morphogenetic Proteins ,medicine ,Animals ,Chordin ,Endoderm ,Noggin ,Body Patterning - Abstract
Although some progress in understanding the molecular mechanisms of early embryogenesis has been made, a few outstanding issues remain to be clarified. Of particular interest is whether dorsal–ventral patterning of the endoderm is also controlled by BMP signaling. It appears quite likely that TGFβ signals are essential for endodermal patterning (3xGamer, L and Wright, C. Dev. Biol. 1995; 171: 240–251Crossref | PubMed | Scopus (107)See all References, 7xHenry, G, Brivanlou, I, Kessler, D, Hemmati-Brivanlou, A, and Melton, D. Development. 1996; 122: 1007–1015PubMedSee all References, 13xSasai, Y, Lu, B, Piccolo, S, and De Robertis, E. EMBO J. 1996; 15: 4547–4555PubMedSee all References). Preliminary results suggest that BMP4, chordin, and noggin, the same molecules used in the ectoderm and the mesoderm, also pattern the endoderm (Sasai et al. 1996xSasai, Y, Lu, B, Piccolo, S, and De Robertis, E. EMBO J. 1996; 15: 4547–4555PubMedSee all ReferencesSasai et al. 1996). This suggests that conserved mechanisms of patterning are employed in all three germ layers (Figure 4Figure 4). BMPs are active in many other important biological processes, and it remains to be established whether noggin and chordin are important in BMP action at other times and places. It is unclear why two factors, noggin and chordin, with essentially identical activity are needed when only one might suffice. Relatedly, if there are two, there might be other proteins with similar activity either for BMPs or for other TGFβs. Although it appears that BMP signaling is essential for formation of the ventral side of the embryo, it is unclear what establishes the restricted pattern of BMP expression on the ventral side of the embryo. In addition, it remains unknown what signals establish formation of the organizer or restrict expression of chordin and noggin to the organizer. The best data supports a role for the Wnt signaling pathway in organizer formation, although how this is established is poorly understood (Carnac et al. 1996xCarnac, G, Kodjabachian, L, Gurdon, J, and Lemaire, P. Development. 1996; 122: 3055–3065PubMedSee all ReferencesCarnac et al. 1996references therein). Finally, although we have begun to understand what patterns the ectoderm, mesoderm, and endoderm, we still do not know the nature of the molecule(s) that initially induces formation of the mesoderm.
- Published
- 1997
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42. Mothers against dpp encodes a conserved cytoplasmic protein required in DPP/TGF-β responsive cells
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William M. Gelbart, Jonathan M. Graff, Elena H. Chartoff, Stuart J. Newfeld, and Douglas A. Melton
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Cytoplasm ,Mesoderm ,Embryo, Nonmammalian ,animal structures ,Transcription, Genetic ,Xenopus ,Blotting, Western ,Biology ,Polymerase Chain Reaction ,Mothers against decapentaplegic homolog 2 ,Genes, Reporter ,Transforming Growth Factor beta ,Morphogenesis ,medicine ,Animals ,Drosophila Proteins ,Molecular Biology ,Transcription factor ,Decapentaplegic ,RNA-Directed DNA Polymerase ,biology.organism_classification ,Molecular biology ,DNA-Binding Proteins ,Repressor Proteins ,Enhancer Elements, Genetic ,medicine.anatomical_structure ,Insect Hormones ,Drosophila ,Endoderm ,Signal transduction ,Drosophila Protein ,Signal Transduction ,Transcription Factors ,Developmental Biology - Abstract
The proteins necessary for signal transduction in cells responding to ligands of the TGF-β family are largely unknown. We have previously identified Mad (Mothers against dpp), a gene that interacts with the TGF-β family member encoded by decapentaplegic (dpp) in Drosophila. Assay of Mad’s role in the DPP-dependent events of embryonic midgut development demonstrates that Mad is required for any response of the visceral mesoderm or endoderm to DPP signals from the visceral mesoderm. Replacement of the normal DPP promoter with a heterologous (hsp70) promoter fails to restore DPP-dependent responses in Mad mutant midguts. Experiments utilizing Mad transgenes regulated by tissue-specific promoters show that MAD is required specifically in cells responding to DPP. Immunohistochemical studies localize MAD to the cytoplasm in all tissues examined. Experiments in Xenopus embryos demonstrate that Drosophila MAD can function in the signaling pathway of BMP-4, a vertebrate homolog of dpp. Based on these results, we propose that Mad is a highly conserved and essential element of the DPP signal transduction pathway.
- Published
- 1996
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43. Xenopus Mad Proteins Transduce Distinct Subsets of Signals for the TGFβ Superfamily
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Jonathan M. Graff, Anu Bansal, and Douglas A. Melton
- Subjects
Cytoplasm ,Mesoderm ,Embryo, Nonmammalian ,animal structures ,Microinjections ,Xenopus ,Molecular Sequence Data ,Xenopus Proteins ,Polymerase Chain Reaction ,Bone morphogenetic protein 2 ,General Biochemistry, Genetics and Molecular Biology ,Smad1 Protein ,Mothers against decapentaplegic homolog 2 ,Transforming Growth Factor beta ,TGF beta signaling pathway ,medicine ,Animals ,RNA, Messenger ,Cloning, Molecular ,Cell Nucleus ,Base Sequence ,Sequence Homology, Amino Acid ,biology ,Biochemistry, Genetics and Molecular Biology(all) ,Gene Expression Regulation, Developmental ,Transforming growth factor beta superfamily ,biology.organism_classification ,Molecular biology ,DNA-Binding Proteins ,Repressor Proteins ,medicine.anatomical_structure ,embryonic structures ,NODAL ,Signal Transduction ,Transcription Factors - Abstract
Xenopus cDNAs homologous to the Drosophila Mad gene and C. elegans CEM genes have been cloned and functionally analyzed by microinjection into frog embryos. The results show that these genes (Xmad) encode intracellular proteins that act downstream of TGF beta superfamily ligands. Most interesting is the fact that different Xmad proteins produce distinct biological responses. Xmad1 produces ventral mesoderm, apparently transducing a signal for BMP2 and BMP4, whereas Xmad2 induces dorsal mesoderm like Vg1, activin, and nodal. These results suggest that an individual Xmad protein waits poised in the cytoplasm for instruction from a distinct subset of TGF beta ligands and then conveys specific information to the nucleus.
- Published
- 1996
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44. A mouse model of rhabdomyosarcoma originating from the adipocyte lineage
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David Finkelstein, Mark E. Hatley, Jonathan M. Graff, Rene L. Galindo, Wei Tang, Eric N. Olson, Douglas P. Millay, Ning Liu, and Matthew R. Garcia
- Subjects
musculoskeletal diseases ,0303 health sciences ,Cancer Research ,Skeletal muscle ,Cell Biology ,Cell cycle ,Biology ,medicine.disease ,musculoskeletal system ,Hedgehog signaling pathway ,Article ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,medicine ,Cancer research ,Alveolar rhabdomyosarcoma ,Myocyte ,Embryonal rhabdomyosarcoma ,Rhabdomyosarcoma ,Smoothened ,030304 developmental biology - Abstract
SummaryRhabdomyosarcoma (RMS) is an aggressive skeletal muscle-lineage tumor composed of malignant myoblasts that fail to exit the cell cycle and are blocked from fusing into syncytial muscle. Rhabdomyosarcoma includes two histolopathologic subtypes: alveolar rhabdomyosarcoma, driven by the fusion protein PAX3-FOXO1 or PAX7-FOXO1, and embryonal rhabdomyosarcoma (ERMS), which is genetically heterogeneous. Here, we show that adipocyte-restricted activation of Sonic hedgehog signaling through expression of a constitutively active Smoothened allele in mice gives rise to aggressive skeletal muscle tumors that display the histologic and molecular characteristics of human ERMS with high penetrance. Our findings suggest that adipocyte progenitors can be a cell of origin for Sonic hedgehog-driven ERMS, showing that RMS can originate from nonskeletal muscle precursors.
- Published
- 2012
45. SnapShot: adipocyte life cycle
- Author
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Jonathan M. Graff, Yuwei Jiang, and A-Young Jo
- Subjects
0303 health sciences ,Cell growth ,Biochemistry, Genetics and Molecular Biology(all) ,Cellular differentiation ,Stem Cells ,Cell Differentiation ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,Snapshot (photography) ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Adipose Tissue ,030220 oncology & carcinogenesis ,Adipocyte ,Adipocytes ,Animals ,Humans ,Obesity ,030304 developmental biology ,Cell Proliferation - Published
- 2012
46. Osteoclast Progenitors Reside in PPARγ-Expressing Bone Marrow Cell Population
- Author
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Yihong Wan, Wei Wei, Daniel Zeve, Xueqian Wang, Yang Du, Wei Tang, Paul C Dechow, and Jonathan M Graff
- Published
- 2011
- Full Text
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47. Biphasic and Dosage-Dependent Regulation of Osteoclastogenesis by β-Catenin
- Author
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Xueqian Wang, Yang Du, Yihong Wan, Joseph E. Zerwekh, Paul C. Dechow, Jae Myoung Suh, Jonathan M. Graff, Wei Wei, and Daniel Zeve
- Subjects
Macrophage colony-stimulating factor ,Male ,Beta-catenin ,Cellular differentiation ,Cathepsin K ,Gene Expression ,Osteoclasts ,Mice, Transgenic ,Collagen Type I ,Mice ,Osteoclast ,Proto-Oncogenes ,medicine ,Animals ,Molecular Biology ,Cells, Cultured ,beta Catenin ,biology ,Tibia ,Macrophage Colony-Stimulating Factor ,RANK Ligand ,Wnt signaling pathway ,JNK Mitogen-Activated Protein Kinases ,Cell Differentiation ,Cell Biology ,Articles ,MDS1 and EVI1 Complex Locus Protein ,Peptide Fragments ,DNA-Binding Proteins ,Enzyme Activation ,GATA2 Transcription Factor ,PPAR gamma ,Radiography ,medicine.anatomical_structure ,Catenin ,Osteopetrosis ,Cancer research ,biology.protein ,Phosphorylation ,Transcription Factors - Abstract
Wnt/β-catenin signaling is a critical regulator of skeletal physiology. However, previous studies have mainly focused on its roles in osteoblasts, while its specific function in osteoclasts is unknown. This is a clinically important question because neutralizing antibodies against Wnt antagonists are promising new drugs for bone diseases. Here, we show that in osteoclastogenesis, β-catenin is induced during the macrophage colony-stimulating factor (M-CSF)-mediated quiescence-to-proliferation switch but suppressed during the RANKL-mediated proliferation-to-differentiation switch. Genetically, β-catenin deletion blocks osteoclast precursor proliferation, while β-catenin constitutive activation sustains proliferation but prevents osteoclast differentiation, both causing osteopetrosis. In contrast, β-catenin heterozygosity enhances osteoclast differentiation, causing osteoporosis. Biochemically, Wnt activation attenuates whereas Wnt inhibition stimulates osteoclastogenesis. Mechanistically, β-catenin activation increases GATA2/Evi1 expression but abolishes RANKL-induced c-Jun phosphorylation. Therefore, β-catenin exerts a pivotal biphasic and dosage-dependent regulation of osteoclastogenesis. Importantly, these findings suggest that Wnt activation is a more effective treatment for skeletal fragility than previously recognized that confers dual anabolic and anti-catabolic benefits.
- Published
- 2011
- Full Text
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48. Wnt signaling activation in adipose progenitors promotes insulin-independent muscle glucose uptake
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Douglas P. Millay, Ajin Lim, Myrna J. Martinez, Yihong Wan, Renée M. McKay, Wei Tang, Drew Stenesen, Linda J. Williams, Eric N. Olson, Daniel Zeve, Jin Seo, Jae Myoung Suh, Eric D. Berglund, and Jonathan M. Graff
- Subjects
medicine.medical_specialty ,Lipodystrophy ,Physiology ,Glucose uptake ,medicine.medical_treatment ,Adipose tissue ,Carbohydrate metabolism ,AMP-Activated Protein Kinases ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,AMP-activated protein kinase ,Internal medicine ,medicine ,Adipocytes ,Animals ,Insulin ,Cell Lineage ,Molecular Biology ,Wnt Signaling Pathway ,beta Catenin ,030304 developmental biology ,Adiposity ,0303 health sciences ,biology ,Muscles ,Stem Cells ,Glucose transporter ,Wnt signaling pathway ,AMPK ,Biological Transport ,Cell Differentiation ,Cell Biology ,Mice, Mutant Strains ,Cell Compartmentation ,PPAR gamma ,Endocrinology ,Glucose ,Culture Media, Conditioned ,Mutation ,biology.protein ,Stromal Cells ,030217 neurology & neurosurgery - Abstract
SummaryAdipose tissues provide circulating nutrients and hormones. We present in vivo mouse studies highlighting roles for Wnt signals in both aspects of metabolism. β-catenin activation in PPARγ-expressing fat progenitors (PBCA) decreased fat mass and induced fibrotic replacement of subcutaneous fat specifically. In spite of lipodystrophy, PBCA mice did not develop the expected diabetes and hepatosteatosis, but rather exhibited improved glucose metabolism and normal insulin sensitivity. Glucose uptake was increased in muscle independently of insulin, associated with cell-surface translocation of glucose transporters and AMPK activation. Ex vivo assays showed these effects were likely secondary to blood-borne signals since PBCA sera or conditioned media from PBCA fat progenitors enhanced glucose uptake and activated AMPK in muscle cultures. Thus, adipose progenitor Wnt activation dissociates lipodystrophy from dysfunctional metabolism and highlights a fat-muscle endocrine axis, which may represent a potential therapy to lower blood glucose and improve metabolism.
- Published
- 2011
49. Fighting fat with fat: the expanding field of adipose stem cells
- Author
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Daniel Zeve, Wei Tang, and Jonathan M. Graff
- Subjects
Lipodystrophy ,Cellular differentiation ,Adipose tissue ,Hyperlipidemias ,Biology ,Article ,Lineage tracing ,Genetics ,Adipocytes ,Compartment (development) ,Animals ,Humans ,Stem Cell Niche ,Hematopoietic Stem Cell Mobilization ,Cell Proliferation ,Extramural ,Gene Expression Regulation, Developmental ,Cell Differentiation ,Cell Biology ,Antigens, Differentiation ,Cell biology ,Adult Stem Cells ,Adipose Tissue ,Immunology ,Tissue Transplantation ,Molecular Medicine ,Blood Vessels ,Stem cell ,Adult stem cell - Abstract
We are in the midst of a dire, unprecedented, and global epidemic of obesity and secondary sequelae, most prominently diabetes and hyperlipidemia. Underlying this epidemic is the most hated of cells, adipocytes, and their inherent dynamic ability to expand and renew. This capacity highlights a heretofore undefined stem compartment. Recent in vivo studies, relying upon lineage tracing and flow cytometry methods, have begun to unravel the identity of adipose stem cells, their niche, and the dynamism central to adipose expansion. Thus, the field is moving in a direction that may allow us to manipulate adipose stem cells to beneficial therapeutic ends.
- Published
- 2009
50. The transcription factor ATF4 regulates glucose metabolism in mice through its expression in osteoblasts
- Author
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Dae Young Jung, Jason K. Kim, Tatsuya Yoshizawa, Mathieu Ferron, Jonathan M. Graff, Daisuke Kajimura, Gerard Karsenty, Jin Seo, and Eiichi Hinoi
- Subjects
medicine.medical_specialty ,Transgene ,medicine.medical_treatment ,Osteocalcin ,Gene Expression ,Mice, Transgenic ,Activating Transcription Factor 4 ,Carbohydrate metabolism ,Models, Biological ,Mice ,Internal medicine ,Gene expression ,Insulin Secretion ,medicine ,Animals ,Insulin ,Transcription factor ,Mice, Knockout ,Osteoblasts ,biology ,ATF4 ,General Medicine ,Mice, Mutant Strains ,Mice, Inbred C57BL ,Endocrinology ,Glucose ,Phenotype ,biology.protein ,Research Article - Abstract
The recent demonstration that osteoblasts have a role in controlling energy metabolism suggests that they express cell-specific regulatory genes involved in this process. Activating transcription factor 4 (ATF4) is a transcription factor that accumulates predominantly in osteoblasts, where it regulates virtually all functions linked to the maintenance of bone mass. Since Atf4-/- mice have smaller fat pads than littermate controls, we investigated whether ATF4 also influences energy metabolism. Here, we have shown, through analysis of Atf4-/- mice, that ATF4 inhibits insulin secretion and decreases insulin sensitivity in liver, fat, and muscle. Several lines of evidence indicated that this function of ATF4 occurred through its osteoblastic expression. First, insulin sensitivity is enhanced in the liver of Atf4-/- mice, but not in cultured hepatocytes from these mice. Second, mice overexpressing ATF4 in osteoblasts only [termed here alpha1(I)Collagen-Atf4 mice] displayed a decrease in insulin secretion and were insulin insensitive. Third, the alpha1(I)Collagen-Atf4 transgene corrected the energy metabolism phenotype of Atf4-/- mice. Fourth, and more definitely, mice lacking ATF4 only in osteoblasts presented the same metabolic abnormalities as Atf4-/- mice. Molecularly, ATF4 favored expression in osteoblasts of Esp, which encodes a product that decreases the bioactivity of osteocalcin, an osteoblast-specific secreted molecule that enhances secretion of and sensitivity to insulin. These results provide a transcriptional basis to the observation that osteoblasts fulfill endocrine functions and identify ATF4 as a regulator of most functions of osteoblasts.
- Published
- 2009
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