38 results on '"Xiaoqing Sun"'
Search Results
2. The Two‐Steps Reaction Fluorescent Probe for the Selective Detection of Cysteine and Its Applications**
- Author
-
Xueliang Liu, Haiyuan Wei, Mengdi Yan, Guangfan Hai, Qin Li, Ruifang Yan, Shan Zhao, Xiaoxia Zhao, Xiaoqing Sun, and Tao Zhang
- Subjects
Humans ,Molecular Medicine ,Bioengineering ,Cysteine ,General Chemistry ,General Medicine ,Glutathione ,Molecular Biology ,Biochemistry ,Fluorescent Dyes ,HeLa Cells - Abstract
We reported the specific fluorescent probe (MC-BOD-XDS) with two-steps reaction based on monosulfanyl-coumarin-BODIPY for selective detection of cysteine, high activity sulfanyl-coumarin as the multiple reaction group instead of a group internal standard fluorophore. The reaction mechanism of MC-BOD-XDS for detecting cysteine was different from the reported probes about the nucleophilic aromatic substitution reaction (SNAr) of chlorinated BODIPY. The fluorescent color of MC-BOD-XDS changed from yellow to red, and then to orange. The linear calibration diagram showed that it can potentially be used for quantitatively detection of Cys. Its potential applications were demonstrated by employing it for detection of Cys in artificial urine and in fluorescent imaging in HeLa cells.
- Published
- 2022
- Full Text
- View/download PDF
3. Characterization of the complete mitochondrial genome of Dongyangjiang White-toothed Shrew, Crocidura dongyangjiangensis (Eulipotyphla: Soricidae) and its phylogenetic analysis
- Author
-
Yuchun Li, Xiaoqing Sun, Yaoyao Li, Guanze Liu, Haotian Li, Xinghan Lin, and Guochen Zhang
- Subjects
0106 biological sciences ,0301 basic medicine ,Mitochondrial DNA ,biology ,Phylogenetic tree ,Shrew ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,White (mutation) ,03 medical and health sciences ,030104 developmental biology ,stomatognathic system ,Evolutionary biology ,Crocidura ,biology.animal ,Genetics ,Molecular Biology - Abstract
The complete mitochondrial genome of the Dongyangjiang White-toothed Shrew (Crocidura dongyangjiangensis), a newly discovered Crocidura species, is sequenced and characterized. The total length of ...
- Published
- 2021
- Full Text
- View/download PDF
4. Characterization of a novel COL10A1 variant associated with Schmid‐type metaphyseal chondrodysplasia and a literature review
- Author
-
Xiaoqing Sun, Jiajun Zhao, Guimei Li, Li Fang, Chao Xu, Xiuyun Jiang, Yanzhou Wang, Shuping Wang, Huixiao Wu, Ning Wang, and Yangyang Yao
- Subjects
0301 basic medicine ,Proband ,Male ,Heterozygote ,Metaphyseal chondrodysplasia ,In silico ,030105 genetics & heredity ,Biology ,skeletal dysplasia ,QH426-470 ,Osteochondrodysplasias ,Short stature ,Genetic analysis ,COL10A1 ,03 medical and health sciences ,Collagen, type X, alpha 1 ,medicine ,Genetics ,Humans ,Molecular Biology ,Gene ,Genetics (clinical) ,Original Articles ,medicine.disease ,schmid‐type metaphyseal chondrodysplasia ,short stature ,030104 developmental biology ,Phenotype ,variant ,Dysplasia ,Child, Preschool ,Mutation ,Original Article ,medicine.symptom ,Protein Multimerization ,Collagen Type X - Abstract
Background Schmid‐type metaphyseal chondrodysplasia (SMCD) is a rare autosomal dominant skeletal dysplasia caused by heterozygous mutations in COL10A1, the gene which encodes collagen type X alpha 1 chain. However, its genotype–phenotype relationship has not been fully determined. Subjects and Methods The proband is a 2‐year‐old boy, born of non‐consanguineous Chinese parents. We conducted a systematic analysis of the clinical and radiological characteristics and a follow‐up study of the proband. Whole‐exome sequencing was applied for the genetic analysis, together with bioinformatic analysis of predicted consequences of the identified variant. A homotrimer model was built to visualize the affected region and predict possible outcomes of this variant. Furthermore, a literature review and genotype–phenotype analysis were performed by online searching all cases with SMCD. Results A novel heterozygous variant (NM_000493.4: c.1863_1866delAATG, NP_000484.2: p.(Met622 Thrfs*54)) was identified in COL10A1 gene in the affected child. And it was predicted to be pathogenic by in silico analysis. Protein modeling revealed that the variant was located in the NC1 domain, which was predicted to produce truncated collagen and impair the trimerization of collagen type X alpha 1 chain and combination with molecules in the matrix. Moreover, genotype–phenotype correlation analysis demonstrated that patients with truncating variants or variants in NC1 domain often presented earlier onset and severer symptoms compared with those with non‐truncating or variants in non‐NC1 domains. Conclusion The NC1 domain of COL10A1 was proved to be the hotspot region underlying SMCD, patients with variants in NC1 domain were more likely to present severer manifestations at an earlier age., This study characterized a novel COL10A1 variant (c.1863_1866delAATG, p.M622 Tfs*54) associated with Schmid type metaphyseal chondrodysplasia in a two‐year‐old Chinese patient. The novel variant was predicted to impair the trimerization of collagen X (α1) and combination with molecules in the matrix by in silico analysis. The NC1 domain of COL10A1 was a key region underlying SMCD, patients with NC1 mutations tend to present severer manifestations at earlier age.
- Published
- 2021
5. Microbiota restoration reduces antibiotic-resistant bacteria gut colonization in patients with recurrent Clostridioides difficile infection from the open-label PUNCH CD study
- Author
-
Amy Langdon, Drew J. Schwartz, Christopher Bulow, Xiaoqing Sun, Tiffany Hink, Kimberly A. Reske, Courtney Jones, Carey-Ann D. Burnham, Erik R. Dubberke, Gautam Dantas, and for the CDC Prevention Epicenter Program
- Subjects
0301 basic medicine ,Time Factors ,lcsh:QH426-470 ,medicine.drug_class ,Antibiotic resistance ,030106 microbiology ,Antibiotics ,lcsh:Medicine ,Biology ,Gut flora ,Multidrug resistance ,Microbiology ,Fecal microbiota transplantation ,03 medical and health sciences ,Feces ,Recurrence ,Genetics ,medicine ,Humans ,Microbiome ,Molecular Biology ,Genetics (clinical) ,Phylogeny ,Principal Component Analysis ,Bacteria ,Clostridioides difficile ,Research ,lcsh:R ,Drug Resistance, Microbial ,biology.organism_classification ,Tissue Donors ,Resistome ,Gastrointestinal Microbiome ,Intestines ,lcsh:Genetics ,030104 developmental biology ,Metagenomics ,Clostridium Infections ,Molecular Medicine - Abstract
Background Once antibiotic-resistant bacteria become established within the gut microbiota, they can cause infections in the host and be transmitted to other people and the environment. Currently, there are no effective modalities for decreasing or preventing colonization by antibiotic-resistant bacteria. Intestinal microbiota restoration can prevent Clostridioides difficile infection (CDI) recurrences. Another potential application of microbiota restoration is suppression of non-C. difficile multidrug-resistant bacteria and overall decrease in the abundance of antibiotic resistance genes (the resistome) within the gut microbiota. This study characterizes the effects of RBX2660, a microbiota-based investigational therapeutic, on the composition and abundance of the gut microbiota and resistome, as well as multidrug-resistant organism carriage, after delivery to patients suffering from recurrent CDI. Methods An open-label, multi-center clinical trial in 11 centers in the USA for the safety and efficacy of RBX2660 on recurrent CDI was conducted. Fecal specimens from 29 of these subjects with recurrent CDI who received either one (N = 16) or two doses of RBX2660 (N = 13) were analyzed secondarily. Stool samples were collected prior to and at intervals up to 6 months post-therapy and analyzed in three ways: (1) 16S rRNA gene sequencing for microbiota taxonomic composition, (2) whole metagenome shotgun sequencing for functional pathways and antibiotic resistome content, and (3) selective and differential bacterial culturing followed by isolate genome sequencing to longitudinally track multidrug-resistant organisms. Results Successful prevention of CDI recurrence with RBX2660 correlated with taxonomic convergence of patient microbiota to the donor microbiota as measured by weighted UniFrac distance. RBX2660 dramatically reduced the abundance of antibiotic-resistant Enterobacteriaceae in the 2 months after administration. Fecal antibiotic resistance gene carriage decreased in direct relationship to the degree to which donor microbiota engrafted. Conclusions Microbiota-based therapeutics reduce resistance gene abundance and resistant organisms in the recipient gut microbiome. This approach could potentially reduce the risk of infections caused by resistant organisms within the patient and the transfer of resistance genes or pathogens to others. Trial registration ClinicalTrials.gov, NCT01925417; registered on August 19, 2013.
- Published
- 2021
6. Biological properties of sulfanilamide-loaded alginate hydrogel fibers based on ionic and chemical crosslinking for wound dressings
- Author
-
Yanhong Ding, Wenli Gong, Chao Ma, Lin Liu, Xiaoqing Sun, and Yanan Ma
- Subjects
Biocompatibility ,Chemical Phenomena ,Alginates ,Ionic bonding ,macromolecular substances ,02 engineering and technology ,complex mixtures ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Adsorption ,Sulfanilamide ,Structural Biology ,medicine ,Cytotoxicity ,Molecular Biology ,030304 developmental biology ,Mechanical Phenomena ,Ions ,0303 health sciences ,Wound Healing ,Spectrum Analysis ,technology, industry, and agriculture ,Hydrogels ,General Medicine ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,Bandages ,Anti-Bacterial Agents ,Drug Liberation ,Cross-Linking Reagents ,chemistry ,Chemical engineering ,Glutaraldehyde ,Swelling ,medicine.symptom ,0210 nano-technology ,Antibacterial activity ,medicine.drug - Abstract
In this work, alginate hydrogel fibers loading sulfanilamide were proposed using a combination of Ca2+ ions and glutaraldehyde crosslinking to develop an efficient wound dressing. The structure, mechanical properties, absorbency, in vitro drug release and cytotoxicity of the proposed alginate hydrogel fibers were investigated systematically. The results indicated that crosslinking with glutaraldehyde can efficiently enhance the mechanical properties of the alginate hydrogel fibers, and reduce their swelling degree which is beneficial for hydrogel fibers to obtain adjustable fluid adsorption capacity, sustained drug release feature over hydrogel fibers crosslinked only by Ca2+ ions. Antibacterial activity assay demonstrated the bactericidal ability of the alginate hydrogel fibers towards S. aureus and E. coli with the highest antibacterial rate of 99.9%. Furthermore, a preliminary trial of papermaking process for producing alginate hydrogel mats showed the workability and the applicability of the mechanically tough hydrogel fibers. Cytotoxicity assay indicated the enhancement of cell adhesion and proliferation, revealing the non-cytotoxicity and biocompatibility of the alginate hydrogel mats. Based on the excellent mechanical strength, adjustable fluid adsorption capacity, sustained drug release, and biocompatibility, the bi-crosslinked alginate hydrogel fibers had a promising application as ideal wound dressings in clinic.
- Published
- 2020
7. MicroRNA-27a functions as a tumor suppressor in renal cell carcinoma by targeting epidermal growth factor receptor
- Author
-
Junnian Zheng, Xiaolei Sun, Yue-Yan Li, Xiaoqing Sun, Ren-Fu Chen, Jiacun Chen, and Jie Li
- Subjects
0301 basic medicine ,Cancer Research ,Oncogene ,biology ,Cell growth ,Cell migration ,Articles ,Cell cycle ,urologic and male genital diseases ,medicine.disease_cause ,Molecular biology ,female genital diseases and pregnancy complications ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Tumor progression ,030220 oncology & carcinogenesis ,medicine ,Cancer research ,biology.protein ,Epidermal growth factor receptor ,Carcinogenesis ,A431 cells - Abstract
Numerous studies have suggested that microRNAs (miRNAs) are vital in the development of various types of human cancers, including renal cell carcinoma (RCC), and the regulation of tumor progression and invasion. However, the effect of miRNA-27a (miR-27a) on the tumorigenesis of RCC is unclear. The aim of the present study was to investigate the function of miR-27a and identify its possible target genes in RCC cells. In the present study, cell proliferation, migration and invasion and the percentage of apoptotic cells were detected by methylthiazol tetrazolium assays, Annexin V analysis, wound-healing assays and Transwell invasion assays. Western blot analysis was performed to validate the protein expression level and assess whether the epidermal growth factor receptor (EGFR) was a target gene of miR-27a. A tumor xenograft animal model was used to detect the role of miR-27a on RCC cell growth in vivo. The present study demonstrated that miR-27a significantly suppressed human RCC 786-O cell proliferation and induced cell apoptosis. Restoration of miR-27 also resulted in 786-O cell migration and invasion inhibition. Furthermore, upregulated miR-27a attenuated RCC tumor growth in the tumor xenograft animal model. The present results suggested that miR-27a functions as a tumor suppressor in RCC. The western blot analysis assay revealed that EGFR was a novel target of miR-27a. The growth suppression of RCC cells was attributed partly to the downregulation of the cell cycle by ERFR inhibition. The present findings may aid in the understanding of the molecular mechanism of miR-27a in the tumorigenesis of RCC, and may provide novel diagnostic and therapeutic options for RCC.
- Published
- 2016
- Full Text
- View/download PDF
8. Impact of Amoxicillin-Clavulanate followed by Autologous Fecal Microbiota Transplantation on Fecal Microbiome Structure and Metabolic Potential
- Author
-
Kimberly A. Reske, Carey-Ann D. Burnham, Christopher Bulow, Jennie H. Kwon, Sanket Patel, Erik R. Dubberke, Susan R. Jones, Gautam Dantas, Sondra Seiler, Xiaoqing Sun, Meghan A. Wallace, Amy Langdon, and Tiffany Hink
- Subjects
0301 basic medicine ,Adult ,Male ,lcsh:QR1-502 ,microbiome ,Enema ,Biology ,Gut flora ,Amoxicillin-Potassium Clavulanate Combination ,Microbiology ,lcsh:Microbiology ,Host-Microbe Biology ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Antibiotic resistance ,multidrug resistance ,Humans ,Microbiome ,antimicrobial resistance ,Molecular Biology ,Feces ,metagenomics ,Microbiota ,Gastrointestinal Microbiome ,fecal microbiota transplantation ,Middle Aged ,Antimicrobial ,biology.organism_classification ,Editor's Pick ,Healthy Volunteers ,QR1-502 ,3. Good health ,Anti-Bacterial Agents ,Multiple drug resistance ,030104 developmental biology ,Metabolism ,Treatment Outcome ,030211 gastroenterology & hepatology ,Female ,beta-Lactamase Inhibitors ,Autologous Fecal Microbiota Transplantation ,Research Article - Abstract
The spread of multidrug resistance among pathogenic organisms threatens the efficacy of antimicrobial treatment options. The human gut serves as a reservoir for many drug-resistant organisms and their resistance genes, and perturbation of the gut microbiome by antimicrobial exposure can open metabolic niches to resistant pathogens. Once established in the gut, antimicrobial-resistant bacteria can persist even after antimicrobial exposure ceases. Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of amoxicillin-clavulanic acid (Amox-Clav) exposure and autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity. Importantly, we found that metabolic capacity was perturbed even in cases where gross phylogeny remained unchanged and that autoFMT was safe and well tolerated., Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity after exposure to amoxicillin-clavulanic acid (Amox-Clav). Ten healthy participants were enrolled. All received 5 days of Amox-Clav. Half were randomized to autoFMT, derived from stool collected pre-antimicrobial exposure, by enema, and half to saline enema. Participants submitted stool samples pre- and post-Amox-Clav and enema and during a 90-day follow-up period. Shotgun metagenomic sequencing revealed taxonomic composition, resistance gene content, and metabolic capacity. Amox-Clav significantly altered gut taxonomic composition in all participants (n = 10, P 0.05, compared to enrollment). Alterations to microbial metabolic capacity occurred following antimicrobial exposure even in participants without substantial taxonomic disruption, potentially creating open niches for pathogen colonization. Our findings suggest that metabolic potential is an important consideration for complete assessment of antimicrobial impact on the microbiome. AutoFMT was well tolerated and may have contributed to phylogenetic recovery. (This study has been registered at ClinicalTrials.gov under identifier NCT02046525.) IMPORTANCE The spread of multidrug resistance among pathogenic organisms threatens the efficacy of antimicrobial treatment options. The human gut serves as a reservoir for many drug-resistant organisms and their resistance genes, and perturbation of the gut microbiome by antimicrobial exposure can open metabolic niches to resistant pathogens. Once established in the gut, antimicrobial-resistant bacteria can persist even after antimicrobial exposure ceases. Strategies to prevent multidrug-resistant organism (MDRO) infections are scarce, but autologous fecal microbiota transplantation (autoFMT) may limit gastrointestinal MDRO expansion. AutoFMT involves banking one’s feces during a healthy state for later use in restoring gut microbiota following perturbation. This pilot study evaluated the effect of amoxicillin-clavulanic acid (Amox-Clav) exposure and autoFMT on gastrointestinal microbiome taxonomic composition, resistance gene content, and metabolic capacity. Importantly, we found that metabolic capacity was perturbed even in cases where gross phylogeny remained unchanged and that autoFMT was safe and well tolerated.
- Published
- 2018
- Full Text
- View/download PDF
9. Design, synthesis, and biological activity of novel tetrahydropyrazolopyridone derivatives as FXa inhibitors with potent anticoagulant activity
- Author
-
Xiaoqing Sun, Tian Lan, Moyi Liu, Su Guo, Yajing Liu, Yong Wang, Zexin Hong, Linyu Gao, Di Yang, Hongxia Qi, and Ping Gong
- Subjects
Pyridines ,Clinical Biochemistry ,Pharmaceutical Science ,030204 cardiovascular system & hematology ,Pharmacology ,01 natural sciences ,Biochemistry ,Anticoagulant activity ,03 medical and health sciences ,Structure-Activity Relationship ,0302 clinical medicine ,In vivo ,Catalytic Domain ,Drug Discovery ,Potency ,Animals ,Humans ,Molecular Biology ,IC50 ,Blood Coagulation ,Venous Thrombosis ,Binding Sites ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Anticoagulants ,Partially saturated ,Biological activity ,In vitro ,0104 chemical sciences ,Rats ,Molecular Docking Simulation ,Design synthesis ,Drug Design ,Factor Xa ,Molecular Medicine ,Pyrazoles ,Rabbits ,Factor Xa Inhibitors ,Protein Binding - Abstract
A series of novel tetrahydropyrazolopyridone derivatives containing 1,3,4-triazole, triazolylmethyl, and partially saturated heterocyclic moieties as P2 binding element was designed, synthesized, and evaluated in vitro for anticoagulant activity in human and rabbit plasma. All compounds showed moderate to significant potency, and compounds 15b, 15c, 20b, 20c, and 22b were further examined for their inhibitory activity against human FXa in vitro. While compounds 15c and 22b were tested for rat venous thrombosis in vivo. The most promising compound 15c, with an IC50 (FXa) value of 0.14μM and 98% inhibition rate, warranted further investigation as an FXa inhibitor.
- Published
- 2017
10. O-GlcNAcylation is increased in prostate cancer tissues and enhances malignancy of prostate cancer cells
- Author
-
Leina Ma, Haiyan Liu, Jiangang Gao, Wengong Yu, Xinling Zhang, Yuchao Gu, Cuifang Han, and Xiaoqing Sun
- Subjects
Male ,PCA3 ,Cancer Research ,N-Acetylglucosaminyltransferases ,medicine.disease_cause ,Biochemistry ,Acetylglucosamine ,Malignant transformation ,Prostate cancer ,Cell Movement ,Prostate ,Cancer stem cell ,Cell Line, Tumor ,Pancreatic cancer ,Genetics ,medicine ,Humans ,Promoter Regions, Genetic ,Molecular Biology ,Cytoskeleton ,business.industry ,Liver Neoplasms ,Prostatic Neoplasms ,Cancer ,Catenins ,Cadherins ,medicine.disease ,Immunohistochemistry ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Oncology ,Cancer research ,Molecular Medicine ,Carcinogenesis ,business - Abstract
O-GlcNAc is an O-linked ?-N-acetylglucosamine moiety attached to the side-chain hydroxyl of a serine or threonine residue in numerous cytoplasmic and nuclear proteins. In this study, we detected the level of O-GlcNAc in prostate, liver and pancreatic cancer tissues, and found that the global O-GlcNAc modification also known as O-GlcNAcylation, is specifically increased in prostate cancer tissues compared to corresponding adjacent tissues. In addition, we found that global O-GlcNAcylation is increased in prostate cancer cells and not in benign prostatic hyperplasia (BPH) epithelial cells. O-GlcNAc enhanced the anchorage-independent growth and the migratory/invasive ability of prostate cancer cells. More importantly, we provide here, for the first time to the best of our knowledge, direct evidence that increased O-GlcNAcylation induces malignant transformation of nontumorigenic (BPH) cells. Furthermore, our study suggested that inhibiting the formation of the E-cadherin/catenin/cytoskeleton complex may underly the O-GlcNAc-induced prostate cancer progression. Overall, these findings indicated that O-GlcNAcylation is increased in prostate, but not in liver and pancreatic cancer tissues, and that O-GlcNAc can enhance the malignancy of prostate cancer cells.
- Published
- 2014
- Full Text
- View/download PDF
11. Design, synthesis, and structure-activity relationship of novel and effective apixaban derivatives as FXa inhibitors containing 1,2,4-triazole/pyrrole derivatives as P2 binding element
- Author
-
Ping Gong, Xiaoqing Sun, Di Yang, Yajing Liu, Minhua Nie, Feng Zhang, Yue Liu, Yulin Wang, Yong Wang, Zhuang Guo, Xuxu Fan, and Yue Li
- Subjects
Models, Molecular ,medicine.drug_mechanism_of_action ,Stereochemistry ,Pyridones ,Clinical Biochemistry ,Factor Xa Inhibitor ,Pharmaceutical Science ,010402 general chemistry ,Crystallography, X-Ray ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Structure-Activity Relationship ,In vivo ,Drug Discovery ,medicine ,Moiety ,Structure–activity relationship ,Animals ,Humans ,Pyrroles ,Binding site ,Molecular Biology ,IC50 ,Pyrrole ,Venous Thrombosis ,Binding Sites ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,1,2,4-Triazole ,Triazoles ,0104 chemical sciences ,Rats ,chemistry ,Drug Design ,Factor Xa ,Molecular Medicine ,Pyrazoles ,Rabbits ,Factor Xa Inhibitors - Abstract
Four series of novel and potent FXa inhibitors possessing the 1,2,4-triazole moiety and pyrrole moiety as P2 binding element and dihydroimidazole/tetrahydropyrimidine groups as P4 binding element were designed, synthesized, and evaluated for their anticoagulant activity in human and rabbit plasma in vitro. Most compounds showed moderate to excellent activity. Compounds 14a, 16, 18c, 26c, 35a, and 35b were further examined for their inhibition activity against human FXa in vitro and rat venous thrombosis in vivo. The most promising compound 14a, with an IC50 (FXa) value of 0.15μM and 99% inhibition rate, was identified for further evaluation as an FXa inhibitor.
- Published
- 2016
12. Overexpression of Programmed Death Ligand 1 in Dendritic Cells Inhibits Allogeneic Lymphocyte Activation in Mice
- Author
-
Wenzhi Li, Gang Chen, Hai-Tao Zhu, Renfu Chen, Xiang Wang, and Xiaoqing Sun
- Subjects
Male ,T-Lymphocytes ,T cell ,Gene Expression ,Cell Communication ,Biology ,Lymphocyte Activation ,B7-H1 Antigen ,Flow cytometry ,Mice ,Transplantation Immunology ,PD-L1 ,Immune Tolerance ,medicine ,Animals ,Transplantation, Homologous ,Cytotoxic T cell ,MTT assay ,Transgenes ,Receptor ,Antigen-presenting cell ,Mice, Inbred BALB C ,medicine.diagnostic_test ,Dendritic Cells ,Flow Cytometry ,Molecular biology ,Mice, Inbred C57BL ,Allogeneic Lymphocyte ,medicine.anatomical_structure ,biology.protein ,Surgery ,Lymphocyte Culture Test, Mixed - Abstract
Background Co-stimulatory molecules are pivotal for T cell activation. It is increasingly recognized that programmed death ligand 1 (PD-L1) is a novel co-stimulatory molecule, which raises the question as to whether PD-L1 regulates T cell responses. This study aimed to investigate the inhibitory effects of PD-L1 on T cell activation. Materials and Methods We constructed a transgenic vector containing the complete PD-L1 gene, which interacts with the inhibitory receptor PD-1 in T cell-mediated immune activation. Donor dendritic cells (DCs) derived from C57BL/6 mice were transfected with PD-L1 and mixed with allogeneic, recipient T cells from BALB/c mice. The T cell activation was determined by the MTT assay and T cell proliferation was determined using carboxyfluoroscein succinimidyl ester (CFSE)-labeling following in vitro mixed leukocyte reactions. Results The expression of PD-L1 protein in PD-L1-transfected DCs was 47.97% ± 1.06%, compared with 4.66% ± 0.76% and 5.30% ± 0.60% in blank and negative controls, respectively (P < 0.05). PD-L1 protein was effectively expressed in DCs. Furthermore, in DCs stably transfected with PD-L1, T cell activation was significantly suppressed and T cell proliferation rate was decreased by 35% compared with untransfected DCs (P < 0.05). Conclusion PD-L1 delivers an immunoinhibitory signal, suppressing T cell activation. Overexpression of PD-L1 signaling induces tolerance, which presents a promising immunotherapeutic approach for long-term graft acceptance.
- Published
- 2012
- Full Text
- View/download PDF
13. Proteomic analysis of ubiquitinated proteins in normal hepatocyte cell line Chang liver cells
- Author
-
Ying Luo, Lin Wang, Jiangang Yuan, Jinglan Wang, Lifang Lu, Fengwei Tan, Boqin Qiang, Yun Cai, Yunfei Xie, Jun Wu, Yanhua Gong, Xiaoqing Sun, Xiaozhong Peng, and Bing-e Xu
- Subjects
Proteomics ,Proteasome Endopeptidase Complex ,Proteome ,Molecular Sequence Data ,RNA-binding protein ,Ubiquitin-conjugating enzyme ,Biochemistry ,F-box protein ,Chromatography, Affinity ,Cell Line ,Ubiquitin ,Tandem Mass Spectrometry ,Humans ,Amino Acid Sequence ,Molecular Biology ,Glutathione Transferase ,biology ,Ubiquitination ,RNA-Binding Proteins ,Cell cycle ,Fusion protein ,Cell biology ,Proteasome ,Hepatocytes ,biology.protein - Abstract
Post-translational modification by ubiquitin (Ub) and Ub-like modifiers is one of the most important mechanisms regulating a wide range of cellular processes in eukaryotes. Through mediating 26S proteasome-dependent degradation of substrates, the covalent modification of proteins by multiple Ub (ubiquitination) can regulate many different cellular functions such as transcription, antigen processing, signal transduction and cell cycle. To better understand ubiquitination and its functions, proteomic approaches have been developed to purify and identify more protein substrates. The S5a subunit of the 26S proteasome binds to poly-Ub chains containing four or more Ub. In this study, immobilized GST-S5a fusion protein was used to affinity-purify ubiquitinated proteins from Chang liver cells. The purified proteins were then identified with multi-dimensional LC combined with MS/MS. Eighty-three potential ubiquitination substrates were identified. From these proteins, 19 potential ubiquitination sites on 17 potential substrates were determined. These potential ubiquitination substrates are mainly related to important cellular functions including metabolism, translation and transcription. Our results provide helpful information for further understanding of the relationship between ubiquitination machinery and different cell functions.
- Published
- 2008
- Full Text
- View/download PDF
14. Casein Kinase 1α Interacts with RIP1 and Regulates NF-κB Activation
- Author
-
Jun Wu, Xiaozhong Peng, Luo Ying, Yong Wang, Cuiping Gu, Bing-e Xu, Boqin Qiang, Xin Wang, Fengwei Tan, Hui Wang, Xiaoqing Sun, and Jiangang Yuan
- Subjects
MAP kinase kinase kinase ,Chemistry ,Casein kinase 2, alpha 1 ,ASK1 ,Cyclin-dependent kinase 9 ,Casein kinase 1 ,Casein kinase 2 ,Mitogen-activated protein kinase kinase ,Biochemistry ,TRADD ,Molecular biology - Abstract
Tumor necrosis factor alpha (TNFalpha) triggers a signaling pathway converging on the activation of NF-kappaB, which forms the basis for many physiological and pathological processes. In a kinase gene screen using a NF-kappaB reporter, we observed that overexpression of casein kinase 1alpha (CK1alpha) enhanced TNFalpha-induced NF-kappaB activation, and a CK1alpha kinase dead mutant, CK1alpha (K46A), reduced NF-kappaB activation induced by TNFalpha. We subsequently demonstrated that CK1alpha interacted with receptor interacting protein 1 (RIP1) but not with TRADD, TRAF2, MEKK3, IKKalpha, IKKbeta, or IKKgamma in mammalian cells. RIP1 is an indispensable molecule in TNFalpha/NF-kappaB signaling. We demonstrated that CK1alpha interacted with and phosphorylated RIP1 at the intermediate domain. Finally, we showed that CK1alpha enhanced RIP1-mediated NF-kappaB activation. Taken together, our studies suggest that CK1alpha is another kinase that regulates RIP1 function in NF-kappaB activation.
- Published
- 2007
- Full Text
- View/download PDF
15. Cloning and characterization of a novel caspase-10 isoform that activates NF-κB activity
- Author
-
Xiaoqing Sun, Jun Wu, Ying Luo, Dalong Ma, Xin Wang, Pingzhang Wang, and Hui Wang
- Subjects
Gene isoform ,Molecular Sequence Data ,Caspase 2 ,Biophysics ,Biochemistry ,Caspase 7 ,Gene Expression Regulation, Enzymologic ,Jurkat Cells ,Exon ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Caspase 10 ,Molecular Biology ,Caspase ,Base Sequence ,biology ,NLRP1 ,Alternative splicing ,NF-kappa B ,Molecular biology ,Protein Structure, Tertiary ,Cell biology ,Isoenzymes ,Alternative Splicing ,biology.protein ,HeLa Cells ,Signal Transduction - Abstract
Caspase-10 (also known as Mch4 and FLICE2) is an initiator caspase in the death receptor (DR)-dependent apoptotic pathway. So far six splice variants (caspase-10a-f) have been identified. Here we describe a novel isoform of the caspase-10 family named caspase-10g that is widely expressed in normal human tissues and various cell lines. Caspase-10g consists of 247 amino acids and does not contain the large or small subunit. A caspase-10g-specific exon is present between exon 5 and exon 6, which results in a protein product truncated shortly after the death-effector domain (DED)-containing prodomain. We further show that overexpression of caspase-10g dramatically enhances NF-kappaB activity in a dose- and time-dependent manner. Moreover, caspase-10g, unlike the protease-active caspase-10a, only promotes slight apoptosis when overexpressed in mammalian cells and it has no effect on caspase-10a-mediated apoptosis. Taken together, these results suggest that caspase-10g, as a novel prodomain-only isoform of caspase-10, may play a regulatory role preferentially in the NF-kappaB pathways.
- Published
- 2007
- Full Text
- View/download PDF
16. TRB3 interacts with CtIP and is overexpressed in certain cancers
- Author
-
Xiaoqing Sun, Jianmin Xu, Jian Chen, Jun Wu, Shun Lv, Yan Qin, Fang Shu, Yanjuan Xu, and Bing-e Xu
- Subjects
T-Lymphocytes ,Molecular Sequence Data ,Biophysics ,Cell Cycle Proteins ,Protein Serine-Threonine Kinases ,Biology ,Transfection ,medicine.disease_cause ,Polymerase Chain Reaction ,Biochemistry ,Gene Expression Regulation, Enzymologic ,Cell Line ,Negative regulator ,HeLa ,Neoplasms ,medicine ,Humans ,Multiple tumors ,Molecular Biology ,Protein kinase B ,DNA Primers ,B-Lymphocytes ,Cell cycle regulator ,Endodeoxyribonucleases ,Base Sequence ,Kinase ,Nuclear Proteins ,biology.organism_classification ,Peptide Fragments ,Cell biology ,Gene Expression Regulation, Neoplastic ,Repressor Proteins ,medicine.anatomical_structure ,Carrier Proteins ,Carcinogenesis ,Nucleus ,HeLa Cells ,Plasmids - Abstract
TRB3, a human homolog of Drosophila Tribbles, has been recently shown as a critical negative regulator of Akt and S6 kinase activation in a number of cellular processes. Here we found that TRB3 interacted with an important cell cycle regulator CtIP (CtBP-interacting protein) and the interaction involved the C-terminus of both proteins. Interestingly, TRB3 and CtIP co-localized to the nucleus in HeLa cells and exhibited a unique dot-like pattern. Finally, we demonstrated that TRB3 was overexpressed in multiple tumor tissues. Since CtIP plays important roles in cell cycle checkpoint control and it has been implicated in tumorigenesis, our data suggest that TRB3 may be involved in these biological processes through interacting with CtIP.
- Published
- 2007
- Full Text
- View/download PDF
17. Knockdown of Ki-67 by small interfering RNA leads to inhibition of proliferation and induction of apoptosis in human renal carcinoma cells
- Author
-
Jiacun Chen, Xiaoqing Sun, Dong-Sheng Pei, Junnian Zheng, Rumin Wen, Ya-Feng Sun, Teng-Xiang Ma, Jing-Yi Cao, and Wang Li
- Subjects
Small interfering RNA ,Immunocytochemistry ,Apoptosis ,In situ hybridization ,Biology ,Transfection ,General Biochemistry, Genetics and Molecular Biology ,Western blot ,Cell Line, Tumor ,In Situ Nick-End Labeling ,medicine ,Humans ,Gene Silencing ,RNA, Messenger ,RNA, Small Interfering ,General Pharmacology, Toxicology and Pharmaceutics ,In Situ Hybridization ,Cell Proliferation ,Gene knockdown ,Dose-Response Relationship, Drug ,medicine.diagnostic_test ,Reverse Transcriptase Polymerase Chain Reaction ,Cell growth ,Carcinoma ,General Medicine ,Molecular biology ,Kidney Neoplasms ,Ki-67 Antigen ,Cancer research - Abstract
To investigate the effect of small-interfering RNA (siRNA) targeted against Ki-67, which is an attractive molecular target for cancer therapy, on inhibiting Ki-67 expression and cell proliferation in human renal carcinoma cells (HRCCs), siRNAs were used to inhibit the expression of Ki-67 in HRCCs. Ki-67 mRNA levels were detected by RT-PCR and in situ hybridization analysis. Ki-67 protein levels were detected by Western blot and immunocytochemistry analysis. TUNEL assay was used to measure the apoptosis of carcinoma cells. Results of RT-PCR and in situ hybridization demonstrated reduction of Ki-67 mRNA expression in Ki-67 siRNAs treated 786-0 cells. Similar reduction in Ki-67 protein measured by Western blot and immunocytochemistry was observed in cells transfected with Ki-67 siRNA. Ki-67-siRNA treatment of HRCCs resulted in specific inhibition of proliferation and increased apoptotic cell death. From these findings we conclude that inhibition of Ki-67 expression by siRNA may be a reasonable approach in renal cancer therapy.
- Published
- 2006
- Full Text
- View/download PDF
18. Molecular cloning and characterization of a novel ice gene from Capsella bursa-pastoris
- Author
-
Xinglong Wang, Sixiu Liu, Xiaofen Sun, Li Liu, Kexuan Tang, Xiaoqing Sun, and Xiaojun Liu
- Subjects
Open reading frame ,Rapid amplification of cDNA ends ,biology ,Structural Biology ,Complementary DNA ,Biophysics ,Cold acclimation ,Capsella ,Gene family ,Capsella bursa-pastoris ,biology.organism_classification ,Gene ,Molecular biology - Abstract
A new ice gene (designated as Cbice53, an inducer of CBF expression) was cloned from Capsella bursa-pastoris by rapid amplification of cDNA ends (RACE). The full-length cDNA of Cbice53 was 1811 bp long, with a 1476-bp open reading frame (ORF) encoding a Myc-like protein of 492 amino acids. The predicted CbICE53 protein contained a potential basic helix-loop-helix domain, a nuclear localization signal (NLS), an RNA-binding region (RGG box), and N-glycosylation and kinase phosphorylation sites. Bioinformatic analysis showed that CbICE53 was highly homologous to ICE1 from Arabidopsis thaliana. Transcription of Cbice53 gene was induced transiently during salt and cold treatments, suggesting that it was somehow involved in cold acclimation. The results of our study indicate that the Cbice53 gene is a new member of the ice gene family and may have a role in cold and salt responsiveness in C. bursa-pastoris.
- Published
- 2005
- Full Text
- View/download PDF
19. Effects of125I-labeled peptide nuclear acid targeting Ki67 on the growth of implanted human renal cell carcinoma in nude mice
- Author
-
Song Wu, Junnian Zheng, Xiaoqing Sun, Junjie Liu, Haibiao Lai, and Jiacun Chen
- Subjects
chemistry.chemical_classification ,chemistry ,Apoptosis ,Renal cell carcinoma ,Nucleic acid ,medicine ,Peptide ,Biology ,medicine.disease ,Renal carcinoma ,Molecular biology ,Gene ,Earth-Surface Processes - Abstract
Objective To investigate the potential of125I-labeled anti-sense peptide nucleic acids (125I-AS-PNAs) to inhibit the expression of the Ki-67 gene and growth of implanted human renal carcinoma cells in nude mice.
- Published
- 2004
- Full Text
- View/download PDF
20. RIP3, a Novel Apoptosis-inducing Kinase
- Author
-
Daryl T. Baldwin, Xiaoqing Sun, Tony A. Navas, Timothy A. Stewart, Vishva M. Dixit, and James Lee
- Subjects
endocrine system ,Molecular Sequence Data ,Apoptosis ,Plasma protein binding ,Protein Serine-Threonine Kinases ,Biology ,Biochemistry ,Receptors, Tumor Necrosis Factor ,Antigens, CD ,Receptor-Interacting Protein Serine-Threonine Kinase 2 ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Molecular Biology ,Death domain ,Sequence Homology, Amino Acid ,Kinase ,C-terminus ,NF-kappa B ,Proteins ,Cell Biology ,Molecular biology ,Recombinant Proteins ,Protein kinase domain ,Receptors, Tumor Necrosis Factor, Type I ,Caspases ,Receptor-Interacting Protein Serine-Threonine Kinases ,Tumor necrosis factor alpha ,Signal transduction ,Protein Kinases ,Sequence Analysis ,Protein Binding ,Signal Transduction - Abstract
RIP3 is a novel gene product containing a N-terminal kinase domain that shares extensive homology with the corresponding domain in RIP (receptor-interacting protein) and RIP2. Unlike RIP, which has a C-terminal death domain, and RIP2, which has a C-terminal caspase activation and recruitment domain, RIP3 has a unique C terminus. RIP3 binds RIP through its unique C-terminal segment and by virtue of this interaction is recruited to the tumor necrosis factor (TNF) receptor-1 signaling complex. Previous studies have shown that RIP mediates TNF-induced activation of the anti-apoptotic NF-kappaB pathway. RIP3, however, attenuates both RIP and TNF receptor-1-induced NF-kappaB activation. Overexpression studies revealed RIP3 to be a potent inducer of apoptosis, capable of selectively binding to large prodomain initiator caspases.
- Published
- 1999
- Full Text
- View/download PDF
21. A Human RNA Polymerase II Complex Containing Factors That Modify Chromatin Structure
- Author
-
George Orphanides, Vasily Ogryzko, Yoshihiro Nakatani, Xiaoqing Sun, Danny Reinberg, Helen Cho, Xiang Jiao Yang, and Emma Lees
- Subjects
Saccharomyces cerevisiae Proteins ,Transcription, Genetic ,RNA-dependent RNA polymerase ,Cell Cycle Proteins ,RNA polymerase II ,Protein Serine-Threonine Kinases ,Chromatography, Affinity ,Acetyltransferases ,RNA polymerase I ,Humans ,p300-CBP Transcription Factors ,Phosphorylation ,Molecular Biology ,RNA polymerase II holoenzyme ,Polymerase ,Histone Acetyltransferases ,Transcriptional Regulation ,biology ,Cell Biology ,Cyclin-Dependent Kinase 8 ,Chromatin ,Cyclin-Dependent Kinases ,Biochemistry ,Chromatography, Gel ,biology.protein ,Transcription factor II F ,RNA Polymerase II ,Transcription factor II D ,Small nuclear RNA ,HeLa Cells ,Transcription Factors - Abstract
We have isolated a human RNA polymerase II complex that contains chromatin structure remodeling activity and histone acetyltransferase activity. This complex contains the Srb proteins, the Swi-Snf complex, and the histone acetyltransferases CBP and PCAF in addition to RNA polymerase II. Notably, the general transcription factors are absent from this complex. The complex was purified by two different methods: conventional chromatography and affinity chromatography using antibodies directed against CDK8, the human homolog of the yeast Srb10 protein. Protein interaction studies demonstrate a direct interaction between RNA polymerase II and the histone acetyltransferases p300 and PCAF. Importantly, p300 interacts specifically with the nonphosphorylated, initiation-competent form of RNA polymerase II. In contrast, PCAF interacts with the elongation-competent, phosphorylated form of RNA polymerase II.
- Published
- 1998
- Full Text
- View/download PDF
22. NAT, a Human Complex Containing Srb Polypeptides that Functions as a Negative Regulator of Activated Transcription
- Author
-
Paula Rickert, Yi Zhang, Emma Lees, Helen Cho, Danny Reinberg, Xiaoqing Sun, and William S. Lane
- Subjects
Transcriptional Activation ,DNA, Complementary ,Saccharomyces cerevisiae Proteins ,Macromolecular Substances ,Molecular Sequence Data ,Mediator Complex Subunit 1 ,RNA polymerase II ,MED6 ,Biology ,environment and public health ,MED1 ,Fungal Proteins ,Mediator ,Transcription (biology) ,Cyclins ,Transcriptional regulation ,Animals ,Humans ,Amino Acid Sequence ,Phosphorylation ,Molecular Biology ,Mediator Complex ,Base Sequence ,Sequence Homology, Amino Acid ,Cell Biology ,Molecular biology ,Cyclin-Dependent Kinases ,Cell biology ,Repressor Proteins ,enzymes and coenzymes (carbohydrates) ,Trans-Activators ,Transcription factor II H ,biology.protein ,RNA Polymerase II ,Transcription Factors - Abstract
A complex that represses activated transcription and contains the human homologs of the yeast Srb7, Srb10, Srb11, Rgr1, and Med6 proteins was isolated. The complex is devoid of the Srb polypeptides previously shown to be components of the yeast Mediator complex that functions in transcriptional activation. The complex phosphorylates the CTD of RNA polymerase II (RNAPII) at residues other than those phosphorylated by the kinase of TFIIH. Moreover, the complex specifically interacts with RNAPII. The interaction is not mediated by the CTD of RNAPII, but is precluded by phosphorylation of the CTD. Our results indicate that the complex is a subcomplex of the human RNAPII holoenzyme. We suggest that the RNAPII holoenzyme is a transcriptional control panel, integrating and responding to specific signals to activate or repress transcription.
- Published
- 1998
- Full Text
- View/download PDF
23. Construction and screening of a multi-point site-specific mutant library of subtilisin E with a set of oligonucleotides
- Author
-
Qisong Wang, Jie Zhang, Gutian Xiao, Xiaozhou Wu, Xiaoyang Chen, Xiaoqing Sun, and Xie Yi
- Subjects
endocrine system ,Protease ,Oligonucleotide ,medicine.medical_treatment ,fungi ,Mutant ,Mutagenesis (molecular biology technique) ,Dot blot ,Protein engineering ,Biology ,Molecular biology ,General Biochemistry, Genetics and Molecular Biology ,DNA sequencing ,medicine ,General Agricultural and Biological Sciences ,Site-directed mutagenesis ,General Environmental Science - Abstract
A mutant library of subtilisin E containing random combinations of various mutagenized sites was constructed by one-round mutagenesis with 15 mutagenic oligonucleotides. Mutants were screened through dot blot hybridization and DNA sequencing. A single-point mutant (Met 222Ala) and a three-point (Asn 76Asp/Asn109Ser/ I le 205/Cys) mutant gene from the library were expressed. The mutant proteins exhibited conspicuously improved resistance to oxidation and heat treatment, as reported before. The results show that the library is reliable and very useful for protease subtilisin E engineering.
- Published
- 1997
- Full Text
- View/download PDF
24. SMYD3 as an oncogenic driver in prostate cancer by stimulation of androgen receptor transcription
- Author
-
Cheng Liu, Li Liu, Dawei Xu, Hongbo Ren, Qi Shen, Hainan Liu, Sanyuan Hu, Yidong Fan, Kun Wang, Zhonghua Xu, Jie Chen, Jikai Liu, Keqiang Yan, Xiaoqing Sun, and Chang Wang
- Subjects
Male ,Cancer Research ,Chromatin Immunoprecipitation ,Transcription, Genetic ,Carcinogenesis ,Immunoblotting ,Biology ,medicine.disease_cause ,Real-Time Polymerase Chain Reaction ,Transfection ,Sincalide ,Epigenesis, Genetic ,Small hairpin RNA ,Prostate cancer ,Prostate ,Cell Movement ,Cell Line, Tumor ,medicine ,Humans ,Neoplasm Invasiveness ,RNA, Small Interfering ,Promoter Regions, Genetic ,Cell Proliferation ,Histone-Lysine N-Methyltransferase ,medicine.disease ,Molecular biology ,Immunohistochemistry ,Xenograft Model Antitumor Assays ,Up-Regulation ,Transplantation ,Androgen receptor ,Gene Expression Regulation, Neoplastic ,Prostatic Neoplasms, Castration-Resistant ,medicine.anatomical_structure ,Oncology ,Receptors, Androgen ,Cancer research ,Immunostaining - Abstract
Androgen receptor (AR) is critical for prostate tumorigenesis and is frequently overexpressed during prostate cancer (PC) progression. However, few studies have addressed the epigenetic regulation of AR expression.We analyzed SMYD3 expression in human PC with Western blot and immunohistochemistry. SMYD3 expression was knocked down using short hairpin RNA (shRNA) or small interfering RNA (siRNA). Cell proliferation, colony formation, and apoptosis analyses and xenograft transplantation were performed to evaluate the impact of SMYD3 depletion on PC cells. AR expression and promoter activity were determined using real-time quantitative polymerase chain reaction, western blot, and luciferase reporter assay. AR promoter association with Sp1, SMYD3, and histone modifications was assessed by chromatin immunoprecipitation. Differences in AR mRNA abundance and promoter activity were analyzed using Wilcoxon signed-rank tests, SMYD3 expression was analyzed using with Mann-Whitney U tests for unpaired samples, and tumor weight was analyzed with Student t test. All statistical tests were two-sided.The upregulation of SMYD3 protein expression was observed in seven of eight prostate tumor specimens, compared with matched normal tissues. Immunohistochemical analysis showed a strong SMYD3 staining in the nuclei of PC tissues in eight of 25 (32%) cases and in the cytoplasm in 23 out of 25 (92%) cases, whereas benign prostate tissue exhibited weak immunostaining. Depletion of SMYD3 by siRNA or shRNA inhibited PC cell proliferation (72 hours relative to 24 hours: control shRNA vs SMYD3 shRNA 1: mean fold change = 2.76 vs 1.68; difference = 1.08; 95% confidence interval = 0.78 to 1.38, P.001), colony formation, cell migration, invasion, and xenograft tumor formation. Two functional SMYD3-binding motifs were identified in the AR promoter region.SMYD3 promotes prostate tumorigenesis and mediates epigenetic upregulation of AR expression.
- Published
- 2013
25. The Jujube Genome Provides Insights into Genome Evolution and the Domestication of Sweetness/Acidity Taste in Fruit Trees
- Author
-
Xing Zhao, Zhong Zhang, Li-Zhi Gao, Ruiqiang Li, Xiaoming Pang, Jinbo Zhang, Chunmei Zhang, Xingang Li, Xiao Yin, KangKang Wan, Yang Bai, Zhangjun Fei, Xiaoqing Sun, and Jian Huang
- Subjects
0106 biological sciences ,0301 basic medicine ,Cancer Research ,Plant Science ,Plant Genetics ,01 natural sciences ,Genome ,Domestication ,Database and Informatics Methods ,DNA library construction ,Plant Genomics ,Phylogeny ,Genetics (clinical) ,2. Zero hunger ,biology ,Chromosome Mapping ,Ziziphus ,Agriculture ,Phylogenetic Analysis ,Rosales ,Genomics ,Plants ,Genomic Library Construction ,Ziziphus jujuba ,Taste ,Sequence Analysis ,Genome, Plant ,Research Article ,Biotechnology ,Genome evolution ,lcsh:QH426-470 ,Bioinformatics ,Crops ,DNA construction ,Research and Analysis Methods ,Fruits ,Evolution, Molecular ,03 medical and health sciences ,food ,Botany ,Genetics ,Molecular Biology Techniques ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,Comparative genomics ,Molecular Biology Assays and Analysis Techniques ,Sequence Assembly Tools ,Gene Mapping ,Organisms ,Biology and Life Sciences ,Computational Biology ,Molecular Sequence Annotation ,Comparative Genomics ,15. Life on land ,Genome Analysis ,biology.organism_classification ,food.food ,lcsh:Genetics ,030104 developmental biology ,Fruit ,Rhamnaceae ,Plant Biotechnology ,Sequence Alignment ,Microsatellite Repeats ,Crop Science ,010606 plant biology & botany - Abstract
Jujube (Ziziphus jujuba Mill.) belongs to the Rhamnaceae family and is a popular fruit tree species with immense economic and nutritional value. Here, we report a draft genome of the dry jujube cultivar ‘Junzao’ and the genome resequencing of 31 geographically diverse accessions of cultivated and wild jujubes (Ziziphus jujuba var. spinosa). Comparative analysis revealed that the genome of ‘Dongzao’, a fresh jujube, was ~86.5 Mb larger than that of the ‘Junzao’, partially due to the recent insertions of transposable elements in the ‘Dongzao’ genome. We constructed eight proto-chromosomes of the common ancestor of Rhamnaceae and Rosaceae, two sister families in the order Rosales, and elucidated the evolutionary processes that have shaped the genome structures of modern jujubes. Population structure analysis revealed the complex genetic background of jujubes resulting from extensive hybridizations between jujube and its wild relatives. Notably, several key genes that control fruit organic acid metabolism and sugar content were identified in the selective sweep regions. We also identified S-locus genes controlling gametophytic self-incompatibility and investigated haplotype patterns of the S locus in the jujube genomes, which would provide a guideline for parent selection for jujube crossbreeding. This study provides valuable genomic resources for jujube improvement, and offers insights into jujube genome evolution and its population structure and domestication., Author Summary A balanced sweetness and acidity taste is among the most important characteristics of fruits. It is generally believed that human selection of sweetness plays a crucial role in the process of domestication from wild to cultivated fruit trees. However, the molecular mechanisms underlying fruit taste domestication still remain unclear. It is also unclear whether taste improvement is mainly determined by positive selection of advantageous traits such as sweetness or negative selection of disadvantageous trait such as acidity. Chinese jujube, domesticated from the wild jujube, is an economically important fruit tree crop in China. In this study, we sequenced and assembled the genome of a dry jujube and analyzed the genetic relationship between cultivated and wild jujubes through genome resequencing. Key genes involved in the acid and sugar metabolism were identified in the selective sweep regions. This finding suggested an important domestication pattern in fruit taste and also provided insights into the fruit molecular breeding and improvement.
- Published
- 2016
- Full Text
- View/download PDF
26. Reconstitution of human TFIIA activity from recombinant polypeptides: a role in TFIID-mediated transcription
- Author
-
Michael Sheldon, Danny Reinberg, Dongmin Ma, Xiaoqing Sun, and Kam C. Yeung
- Subjects
DNA, Complementary ,Transcription, Genetic ,Protein Conformation ,TATA box ,Molecular Sequence Data ,genetic processes ,information science ,macromolecular substances ,Biology ,law.invention ,Fungal Proteins ,Transcription (biology) ,law ,Genetics ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Base Sequence ,General transcription factor ,fungi ,Transfection ,TATA-Box Binding Protein ,Molecular biology ,Recombinant Proteins ,In vitro ,Cell biology ,DNA-Binding Proteins ,Transcription Factor TFIIA ,Trans-Activators ,health occupations ,Recombinant DNA ,Transcription Factor TFIID ,Transcription factor II D ,Transcription factor II A ,HeLa Cells ,Transcription Factors ,Developmental Biology - Abstract
Human TFIIA activity is composed of three subunits (alpha, beta, gamma). Here we report the isolation of a human cDNA clone encoding the gamma-subunit and the reconstitution of TFIIA activity from recombinant polypeptides (holo-TFIIA). Protein-protein interaction analysis established that the beta and gamma subunits of TFIIA interact with the TBP component of TFIID. The alpha-subunit is recruited into the complex by association with the gamma-subunit. Functional studies indicate that recombinant TFIIA stimulates basal TFIID-dependent transcription but is without effect on TBP-dependent transcription. Our studies indicate that TFIIA not only functions by physically removing negative components present in TFIID (antirepression), as demonstrated previously, but that it can stimulate basal transcription through components of the TFIID complex. Holo-TFIIA also stimulated activation of transcription in vitro as well as in vivo in transfected HeLa cells.
- Published
- 1994
- Full Text
- View/download PDF
27. Isolation of a cDNA encoding the largest subunit of TFIIA reveals functions important for activated transcription
- Author
-
Arie Admon, Fred Mermelstein, Danny Reinberg, T. Shiroya, Takeshi Imai, Hajime Watanabe, K Oguri, Xiaoqing Sun, Tadashi Wada, and Dongmin Ma
- Subjects
DNA, Complementary ,Transcription, Genetic ,Macromolecular Substances ,Protein subunit ,Blotting, Western ,Molecular Sequence Data ,Saccharomyces cerevisiae ,Biology ,Transcription (biology) ,Complementary DNA ,Genetics ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Peptide sequence ,Base Sequence ,Sequence Homology, Amino Acid ,General transcription factor ,Chromatography, Ion Exchange ,Molecular biology ,Recombinant Proteins ,Cell biology ,DNA-Binding Proteins ,Molecular Weight ,Transcription Factor TFIIA ,Transcription preinitiation complex ,Transcription factor II D ,Transcription factor II A ,Transcription Factors ,Developmental Biology - Abstract
Transcription factor IIA has been shown to interact with the TATA-binding protein and to act early during preinitiation complex formation. The human factor is composed of three subunits (alpha, beta, gamma). A human cDNA clone encoding the largest subunit of TFIIA (alpha) was isolated. The recombinant alpha polypeptide, together with the beta and gamma subunits, was capable of reconstituting TFIIA activity. Studies using antibodies raised against recombinant alpha polypeptide demonstrate that TFIIA can be an integral component of the preinitiation complex. We demonstrate that TFIIA not only interacts with TBP but also can associate with the TFIID complex. Functional assays establish that TFIIA has no apparent role in basal transcription but plays an important role in activation of transcription. Interestingly, amino acid sequence analyses of the beta-subunit demonstrate these residues to be entirely contained within the carboxyl terminus of the cDNA clone encoding the alpha-subunit.
- Published
- 1993
- Full Text
- View/download PDF
28. Inhibition of renal cancer cell growth in vitro and in vivo with oncolytic adenovirus armed short hairpin RNA targeting Ki-67 encoding mRNA
- Author
-
Xiaoqing Sun, Junnian Zheng, Rumin Wen, Shi Z, Dong-Sheng Pei, Mei Dd, Bao-Fu Zhang, Lijun Mao, and Xiao Liu
- Subjects
Oncolytic adenovirus ,Cancer Research ,Small interfering RNA ,Genetic enhancement ,Mice, Nude ,Apoptosis ,Biology ,Virus Replication ,Adenoviridae ,Small hairpin RNA ,Mice ,RNA interference ,Cell Line, Tumor ,Gene silencing ,Animals ,Humans ,RNA, Messenger ,RNA, Neoplasm ,RNA, Small Interfering ,Molecular Biology ,Oncolytic Virotherapy ,Gene knockdown ,Genetic Therapy ,Molecular biology ,Kidney Neoplasms ,Oncolytic virus ,Neoplasm Proteins ,Oncolytic Viruses ,Ki-67 Antigen ,Gene Knockdown Techniques ,Cancer research ,Molecular Medicine ,RNA Interference - Abstract
RNA interference (RNAi) has been proved to be a powerful tool for gene knockdown purpose and holds great promise for the treatment of cancer. Our previous study demonstrated that the reduction of Ki-67 expression by means of chemically synthesized siRNAs and shRNAs expressed from plasmid resulted in proliferation inhibition in human renal carcinoma cells. In this study, we constructed a novel oncolytic adenovirus-based shRNA expression system, ZD55-Ki67, and explored ZD55-Ki67-mediated RNAi for Ki-67 gene silencing. Our results showed that ZD55-Ki67 could induce silencing of the Ki-67 gene effectively, allow for efficient tumor-specific viral replication and induce the apoptosis of tumor cells effectively in vitro and in nude mice. We conclude that combining shRNA gene therapy and oncolytic virotherapy can enhance antitumor efficacy as a result of synergism between CRAd oncolysis and shRNA antitumor responses.
- Published
- 2008
29. Effects of peptide nucleic acids against Ki-67 gene on the proliferation and apoptosis of human renal carcinoma cell line
- Author
-
Jia-Chun Chen, Xiaoqing Sun, Song Wu, Junnian Zheng, and Haibiao Lai
- Subjects
Peptide Nucleic Acids ,Biomedical Engineering ,Apoptosis ,Biochemistry ,Biomaterials ,Western blot ,Cell Line, Tumor ,Genetics ,medicine ,Humans ,Carcinoma, Renal Cell ,Earth-Surface Processes ,Cell Proliferation ,TUNEL assay ,medicine.diagnostic_test ,biology ,Cell growth ,Molecular biology ,humanities ,Kidney Neoplasms ,Ki-67 Antigen ,Cell culture ,Ki-67 ,biology.protein ,Nucleic acid ,Immunohistochemistry - Abstract
To investigate the effects of anti-sense peptide nucleic acids (PNAs) targeting Ki-67 gene on modulation of the proliferation and apoptosis of human renal carcinoma cell lines, human renal carcinoma cell line 786-0 cells were treated with anti-sense PNAs at different concentrations (1.0 micromol/L, 2.0 micromol/L, 10.0 micromol/L). The Ki-67 expression of 786-0 cells was detected by immunohistochemical technique and Western blot method respectively. The proliferation of 786-0 cells was studied by cell growth curves and 3H-thymidine incorporation. The apoptosis of 786-0 cells was detected by TUNEL assay. The control groups were treated with anti-sense oligonucleotide (ASODNs) targeting Ki-67 gene. Our results showed that the Ki-67 expression of 786-0 cells treated with anti-sense PNAs (16.9+/-0.7) was significantly inhibited as compared with that of the control groups (28.6+/-0.4) (P0.01). The Ki-67 protein rate of 786-0 cells treated with anti-sense PNAs (42.1 +/-2.2) was significantly reduced when compared with that of the control groups (83.6+/- 1.4) (P0.01). Proliferation of 786-0 cells treated with anti-sense PNAs (20.7+/- 1.5) was significantly inhibited as compared with that of the control groups (58.6+/- 1.4) (P0.01). The apoptosis rate of 786-0 cells treated with anti-sense PNAs (28.7+/- 2.3) was significantly increased higher compared with that of the control groups (13.8 +/- 1.0) (P0.01). From these finds we are led to conclude that anti-sense PNAs targeting Ki-67 gene have stronger effects on the inhibition of the proliferation and induction of apoptosis of human renal carcinoma cells than ASODNs targeting Ki-67 gene. The strategies using anti-sense PNAs targeting Ki-67 gene may be a promising approach for the treatment of renal cell carcinoma.
- Published
- 2007
30. Inhibition of proliferation and induction of apoptosis in human renal carcinoma cells by anti-telomerase small interfering RNAs
- Author
-
Wang Li, Teng-Xiang Ma, Dong-Sheng Pei, Jun-Jie Liu, Ya-Feng Sun, Jun-Nian Zheng, Rui-Fa Han, Qi-Duo Shi, Jiacun Chen, and Xiaoqing Sun
- Subjects
Programmed cell death ,Small interfering RNA ,Telomerase ,Biophysics ,Apoptosis ,Biology ,Transfection ,Biochemistry ,Telomerase RNA component ,Cell Line, Tumor ,Humans ,Telomerase reverse transcriptase ,RNA, Small Interfering ,Carcinoma, Renal Cell ,Cell Proliferation ,Messenger RNA ,RNA ,General Medicine ,Molecular biology ,Kidney Neoplasms ,DNA-Binding Proteins ,Cancer research ,RNA Interference - Abstract
Telomerase is an attractive molecular target for cancer therapy because it is present in most malignant cells but is undetectable in most normal somatic cells. Human telomerase consists of two subunits, an RNA component (hTR) and a human telomerase reverse transcriptase component (hTERT). Small interfering RNA (siRNA), one kind of RNA interferences, has been demonstrated to be an effective method to inhibit target gene expression in human cells. We investigated the effects of siRNA targeting at both hTR and hTERT mRNA on the inhibition of telomerase activity in human renal carcinoma cells (HRCCs). The proliferation and apoptosis of HRCCs were examined. The treatment of HRCCs using hTR and hTERT siRNAs resulted in significant decrease of hTR mRNA, hTERT mRNA and hTERT protein. The siRNA can also inhibit the telomerase activity and the proliferation of HRCCs. Moreover, they can induce apoptotic cell death in a dose-dependent manner. From these findings, we propose that the inhibition of telomerase activity using siRNA targeting hTR and hTERT might be a rational approach in renal cancer therapy.
- Published
- 2006
31. Treatment with vector-expressed small hairpin RNAs against Ki67 RNA-induced cell growth inhibition and apoptosis in human renal carcinoma cells
- Author
-
Dong-Sheng Pei, Dian-Bao Zheng, Rui-Fa Han, Wang Li, Junnian Zheng, Teng-Xiang Ma, Ya-Feng Sun, Jun-Jie Liu, Xiaoqing Sun, and Jiacun Chen
- Subjects
Genetic enhancement ,Genetic Vectors ,Biophysics ,Apoptosis ,Biology ,Transfection ,Biochemistry ,RNA polymerase III ,Cell Line, Tumor ,medicine ,In Situ Nick-End Labeling ,Gene silencing ,Humans ,RNA, Messenger ,RNA, Small Interfering ,Gene ,Cell Proliferation ,Expression vector ,Reverse Transcriptase Polymerase Chain Reaction ,Cancer ,RNA ,General Medicine ,medicine.disease ,Molecular biology ,Kidney Neoplasms ,Ki-67 Antigen ,Cancer research - Abstract
Short hairpin RNAs (shRNAs) transcribed by RNA polymerase III promoters can trigger sequence-selective gene silencing in mammalian cells. By virtue of their excellent function in knocking down expression of cancer-associated genes, shRNAs could be used as new therapeutic agents for cancer. As overexpression of Ki67 in renal cancer has been correlated to a more aggressive tumor phenotype, inhibition of Ki67 protein expression by means of shRNAs seems to be a promising approach for the therapy of renal cancer. In this study, we constructed an expression plasmid encoding shRNAs against the Ki67 gene, named pSilencerKi67, and transfected it into human renal carcinoma cells. The pSilencerKi67 was shown to significantly knock down the expression of the Ki67 gene in human renal carcinoma cells, resulting in inhibiting proliferation and inducing apoptotic cell death that can be maintained for at least 6 d. These findings offer the promise of using vector-based shRNAs against Ki67 in renal cancer gene therapy.
- Published
- 2006
32. Anti-Ki-67 peptide nucleic acid affects the proliferation and apoptosis of human renal carcinoma cells in vitro
- Author
-
Xiaoqing Sun, Wang Li, Wei-Qi Cai, Ya-Feng Sun, Junnian Zheng, Jun-Jie Liu, Jing-Yi Cao, Jia-Chun Chen, and Dong-Sheng Pei
- Subjects
Peptide Nucleic Acids ,Blotting, Western ,Peptide ,Apoptosis ,Biology ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,Cell Line, Tumor ,In Situ Nick-End Labeling ,Humans ,General Pharmacology, Toxicology and Pharmaceutics ,Cell Proliferation ,chemistry.chemical_classification ,Peptide nucleic acid ,Dose-Response Relationship, Drug ,Cell growth ,General Medicine ,Molecular biology ,Immunohistochemistry ,In vitro ,Kidney Neoplasms ,Ki-67 Antigen ,chemistry ,Cell culture ,Nucleic acid ,DNA - Abstract
We treated in vitro human renal carcinoma cells (cell line 786-0) with the lipid-delivered peptide nucleic acids (PNAs) against Ki-67 gene. Corresponding control groups were treated with the antisense oligonucleotides (ASOs) of the same nucleobase sequence, and with mismatched PNAs. In cells treated by anti- Ki-67 PNAs, the Ki-67 expression rate, Ki-67 protein level, cell growth and the DNA synthesis-indicative 3 H-thymidine incorporation rate were lower than in the ASO-treated groups, and reduced significantly compared to untreated controls, whereas the rate of apoptosis was markedly increased by PNA treatment. We conclude that anti- Ki-67 PNA has more strong (than ASO) and dose-dependent effects on the proliferation and apoptosis of human renal carcinoma cells. Our results indicate that the strategy of using PNA against the Ki-67 gene might be a promising approach in renal carcinoma therapy.
- Published
- 2004
33. Kinase RIP3 is dispensable for normal NF-kappa Bs, signaling by the B-cell and T-cell receptors, tumor necrosis factor receptor 1, and Toll-like receptors 2 and 4
- Author
-
Vishva M. Dixit, Xiaoqing Sun, and Kim Newton
- Subjects
endocrine system ,endocrine system diseases ,T-Lymphocytes ,Ripoptosome ,Apoptosis ,Receptors, Cell Surface ,IκB kinase ,Biology ,Receptors, Tumor Necrosis Factor ,RIPK1 ,Mice ,Antigens, CD ,Mammalian Genetic Models with Minimal or Complex Phenotypes ,Animals ,Molecular Biology ,Transcription factor ,Cells, Cultured ,Death domain ,B-Lymphocytes ,Membrane Glycoproteins ,Macrophages ,Toll-Like Receptors ,NF-kappa B ,Cell Differentiation ,Cell Biology ,Molecular biology ,Toll-Like Receptor 2 ,Cell biology ,Killer Cells, Natural ,Protein kinase domain ,Receptors, Tumor Necrosis Factor, Type I ,Receptor-Interacting Protein Serine-Threonine Kinases ,Tumor necrosis factor receptor 1 ,Signal transduction ,Protein Kinases ,Gene Deletion ,Signal Transduction - Abstract
RIP3 was first identified as a protein able to interact with the serine/threonine kinase RIP and as a protein with an N-terminal kinase domain similar to that found in RIP and the related kinase RIP2 (5, 11, 17, 20). Whereas RIP possesses a C-terminal death domain and RIP2 has a C-terminal caspase activation and recruitment domain, RIP3 has a unique C terminus. Transient expression of RIP3 at high levels in cell lines was found to promote apoptosis (5, 11, 17, 20), an outcome that also can be observed with RIP (15). However, studies of RIP-deficient mice have shown that in a physiological setting RIP is essential for tumor necrosis factor (TNF)-induced activation of the IκB kinase (IKK) complex and is antiapoptotic (1, 6). IKK-mediated phosphorylation of the IκBs promotes their ubiquitination and degradation, which allow the NF-κB transcription factors that IκBs sequester in the cytosol to move into the nucleus (3, 4). Consistent with a role for RIP in activation of NF-κB, RIP is a potent activator of NF-κB-dependent reporter genes in transient-overexpression studies. RIP3, by comparison, is a poor activator of such reporter genes and will even inhibit RIP- or TNF-induced NF-κB activation (5, 11, 17, 20). Nevertheless, RIP3 was isolated recently from a mouse thymus expression library in a screen for proteins that could activate an NF-κB-dependent reporter gene (13). Mutagenesis experiments have indicated that interactions between RIP and RIP3 are mediated by a RIP homotypic interaction motif located toward the C terminus of RIP3 and between the kinase and death domains of RIP (18). Disruption of either RIP homotypic interaction motif prevented RIP3 from phosphorylating RIP. It also negated the inhibitory effect of RIP3 on RIP- or TNF-induced NF-κB activation. Phosphorylation of RIP by RIP3 was crucial to the inhibitory action of RIP3 because a kinase-dead form of RIP3 failed to block RIP- or TNF-induced NF-κB activation (18). These results suggested that RIP3, similar to the protein A20 (8), might play a role in limiting the NF-κB-dependent gene transcription that occurs in response to TNF engaging TNF receptor 1 (TNFR-1). To determine the importance of RIP3 to signaling in the whole animal, we have generated RIP3-deficient mice by gene targeting. Mice lacking RIP3 were healthy and fertile and showed no signs of deregulated NF-κB signaling downstream of TNFR-1 or Toll-like receptors 2 and 4 (TLR-2 and -4).
- Published
- 2004
34. Analysis of differentially expressed genes in keloids and normal skin with cDNA microarray
- Author
-
Tong-zhu Sun, Wei Chen, Zhi-li Zhao, Xiaobing Fu, Xiaoqing Sun, and Zhiyong Sheng
- Subjects
Adult ,Male ,Microarray ,Gene Expression ,Biology ,law.invention ,Transforming Growth Factor beta1 ,Keloid ,law ,Transforming Growth Factor beta ,Complementary DNA ,Gene expression ,Nerve Growth Factor ,medicine ,Humans ,skin and connective tissue diseases ,Gene ,Polymerase chain reaction ,Oligonucleotide Array Sequence Analysis ,Skin ,Reverse Transcriptase Polymerase Chain Reaction ,Gene Expression Profiling ,medicine.disease ,Molecular biology ,Reverse transcription polymerase chain reaction ,Child, Preschool ,Surgery ,Female ,DNA microarray - Abstract
Microarray analysis is a popular tool to investigate the function of genes that are responsible for the phenotype of diseases. Keloid is an intricate lesion that is probably modulated by interplay of many genes. We ventured to study the differences of gene expressions between keloids and normal skin with the aid of a cDNA microarray to explore the molecular mechanism underlying keloid formation.The polymerase chain reaction products of 8400 human genes were spotted on a chip in array. The DNAs were then fixed on the glass plate by a series of treatments. Total RNAs were isolated from freshly excised human keloids and normal skins and then were purified to mRNAs by Oligotex. Both the mRNAs from keloids and normal skins were reversely transcribed to cDNAs with the incorporation of fluorescent dUTP for preparing the hybridization probes. The mixed probes were then hybridized to the cDNA microarray. After highly stringent washing, the cDNA microarray was scanned for the fluorescent signals to display the differences between two kinds of tissues.Among 8400 human genes, there were 402 genes (4.79%) with different expression levels between the keloids and normal skins in all cases, 250 genes, including TGF-beta1 and NGF, were upregulated (2.98%) and 152 downregulated (1.81%). Analyses of collagen, fibronectin, proteoglycan, growth factors, and apoptosis-related molecule gene expression confirmed that our molecular data obtained by cDNA microarray were consistent with the published biochemical and clinical observations of keloids. Higher expression of TGF-beta(1) and NGF in keloids versus normal skins was also testified with reverse transcription polymerase chain reaction method.DNA microarray technology is an effective technique in screening for differences in gene expression between keloid and normal skin. Many genes are involved in the formation of keloids. Further analysis of the obtained genes will help to understand the molecular mechanism of keloid formation.
- Published
- 2003
35. Identification of a novel homotypic interaction motif required for the phosphorylation of receptor-interacting protein (RIP) by RIP3
- Author
-
Wayne J. Fairbrother, Xiaoqing Sun, Melissa A. Starovasnik, Jianping Yin, and Vishva M. Dixit
- Subjects
endocrine system ,endocrine system diseases ,Amino Acid Motifs ,digestive system ,Biochemistry ,Receptors, Tumor Necrosis Factor ,Jurkat Cells ,Antigens, CD ,Humans ,Phosphorylation ,Molecular Biology ,Death domain ,chemistry.chemical_classification ,Chemistry ,Kinase ,Tumor Necrosis Factor-alpha ,C-terminus ,NF-kappa B ,nutritional and metabolic diseases ,Proteins ,Cell Biology ,U937 Cells ,Molecular biology ,Receptor Interacting Protein RIP ,Amino acid ,Protein kinase domain ,Receptors, Tumor Necrosis Factor, Type I ,Receptor-Interacting Protein Serine-Threonine Kinases ,Tumor necrosis factor alpha ,Protein Kinases ,hormones, hormone substitutes, and hormone antagonists - Abstract
Receptor-interacting protein (RIP), a Ser/Thr kinase component of the tumor necrosis factor (TNF) receptor-1 signaling complex, mediates activation of the nuclear factor kappaB (NF-kappaB) pathway. RIP2 and RIP3 are related kinases that share extensive sequence homology with the kinase domain of RIP. Unlike RIP, which has a C-terminal death domain, and RIP2, which has a C-terminal caspase activation and recruitment domain, RIP3 possesses a unique C terminus. RIP3 binds RIP through this unique C-terminal segment to inhibit RIP- and TNF receptor-1-mediated NF-kappaB activation. We have identified a unique homotypic interaction motif at the C terminus of both RIP and RIP3 that is required for their association. Sixty-four amino acids within RIP3 and 88 residues within RIP are sufficient for interaction of the two proteins. This interaction is a prerequisite for RIP3-mediated phosphorylation of RIP and subsequent attenuation of TNF-induced NF-kappaB activation.
- Published
- 2001
36. The RNA polymerase II general transcription factors: past, present, and future
- Author
-
Patricia Cortes, S. Kim, Lisa Weis, Thierry Lagrange, Gary LeRoy, Sasha Akoulitchev, Osvaldo Flores, Tae Kyung Kim, George Orphanides, H. Lu, Juan M. Cárcamo, Michael Sheldon, Fred Mermelstein, Richard H. Ebright, Dongmin Ma, Ilho Ha, Edio Maldonado, Xiaoqing Sun, Leigh Zawel, J. A. Inostroza, Ramin Shiekhattar, Ivan Olave, Kam C. Yeung, Ronny Drapkin, Alejandro Merino, Pardeep Kumar, Helen Cho, N Stone, and Danny Reinberg
- Subjects
Models, Molecular ,Transcription, Genetic ,RNA polymerase II ,Biochemistry ,Protein Structure, Secondary ,Genetics ,RNA polymerase I ,Animals ,Humans ,Amino Acid Sequence ,Molecular Biology ,RNA polymerase II holoenzyme ,General transcription factor ,biology ,Chemistry ,DNA ,TATA-Box Binding Protein ,DNA-Binding Proteins ,biology.protein ,Transcription Factor TFIIB ,Nucleic Acid Conformation ,Transcription factor II F ,Transcription factor II E ,RNA Polymerase II ,Transcription factor II D ,Transcription factor II B ,Transcription Factors - Published
- 1999
37. Multiple functional domains of human transcription factor IIB: distinct interactions with two general transcription factors and RNA polymerase II
- Author
-
Edio Maldonado, Danny Reinberg, Ilho Ha, Xiaoqing Sun, Leu Ung Kim, Michael R. Green, and Stefan G. E. Roberts
- Subjects
Molecular Sequence Data ,Oligonucleotides ,RNA polymerase II ,Transcription Factors, TFII ,Genetics ,Humans ,Point Mutation ,RNA polymerase II holoenzyme ,Repetitive Sequences, Nucleic Acid ,biology ,Base Sequence ,TATA-Box Binding Protein ,Molecular biology ,TATA Box ,Cell biology ,DNA-Binding Proteins ,enzymes and coenzymes (carbohydrates) ,Transcription preinitiation complex ,biology.protein ,Transcription Factor TFIIB ,Transcription factor II F ,RNA Polymerase II ,Transcription factor II D ,TATA-binding protein ,Transcription factor II B ,Transcription factor II A ,Developmental Biology ,Transcription Factors - Abstract
Transcription factor IIB (TFIIB) plays a pivotal role in the formation of transcription-competent initiation complexes. TFIIB was found to interact with the TATA-binding protein, the small subunit of TFIIF, and RNA polymerase II. These interactions require distinct domains in TFIIB. Using the gel mobility-shift assay, it was found that the amino terminus of TFIIB was necessary for the formation of complexes containing RNA polymerase II and TFIIF, whereas the carboxy-terminal domain, which is composed of two imperfect direct repeats and includes a putative amphipathic alpha-helix, was sufficient for the formation of complexes containing the TATA-binding protein and TFIIB (DB complex). Protein-protein interaction analyses demonstrate that the amphipathic alpha-helix in TFIIB is important for the interaction with the TATA-binding protein. Specific residues mapping to the carboxyl terminus of the second direct repeat were found to be crucial for the interaction of TFIIB and RNA polymerase II. The interaction with the small subunit of TFIIF was mapped to the amino terminus of TFIIB, which includes a zinc finger.
- Published
- 1993
38. Adapter protein NRBP associates with Jab1 and negatively regulates AP-1 activity
- Author
-
Jun Wu, Zhixin Lin, Hui Wang, Ying Luo, and Xiaoqing Sun
- Subjects
Vesicular Transport Proteins ,Biophysics ,Receptors, Cytoplasmic and Nuclear ,In Vitro Techniques ,Signal transduction ,medicine.disease_cause ,Biochemistry ,Cell Line ,Structural Biology ,Two-Hybrid System Techniques ,Coactivator ,Genetics ,medicine ,Humans ,Jab1 ,Phosphorylation ,Molecular Biology ,Sequence Deletion ,Binding Sites ,COP9 Signalosome Complex ,Chemistry ,Binding protein ,Intracellular Signaling Peptides and Proteins ,JNK Mitogen-Activated Protein Kinases ,NF-kappa B ,Signal transducing adaptor protein ,Cell Biology ,AP-1 ,Molecular biology ,NRBP ,Recombinant Proteins ,Cell biology ,Transcription Factor AP-1 ,Nuclear receptor ,Carcinogenesis ,Protein Kinases ,Peptide Hydrolases - Abstract
Jun activation domain-binding protein 1 (Jab1) is a coactivator of activating protein-1 (AP-1) and is the fifth component of the COP9 signalosome complex. It interacts with a variety of proteins and plays important roles in diverse signaling pathways and cellular function including oncogenesis. We show here that Jab1 interacts in vivo with nuclear receptor binding protein (NRBP), an evolutionarily conserved adapter protein with a kinase-like domain. We further show that NRBP inhibits Jab1-induced phosphorylation of c-Jun and AP-1 activation. Finally, overexpression of NRBP in mammalian cells specifically inhibits AP-1 activation by various stimuli. Taken together, our data suggest that NRBP may be an important negative regulator of Jab1-mediated functions such as gene transcription and tumor progression.
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.