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The identification of genes that confer either extension of life span or accelerate age-related decline was a step forward in understanding the mechanisms of aging and revealed that it is partially controlled by genetics and transcriptional programs. Here, we discovered that the human DNA sequence C16ORF70 encodes a protein, named MYTHO (macroautophagy and youth optimizer), which controls life span and health span. MYTHO protein is conserved from Caenorhabditis elegans to humans and its mRNA was upregulated in aged mice and elderly people. Deletion of the orthologous myt-1 gene in C. elegans dramatically shortened life span and decreased animal survival upon exposure to oxidative stress. Mechanistically, MYTHO is required for autophagy likely because it acts as a scaffold that binds WIPI2 and BCAS3 to recruit and assemble the conjugation system at the phagophore, the nascent autophagosome. We conclude that MYTHO is a transcriptionally regulated initiator of autophagy that is central in promoting stress resistance and healthy aging., Introduction In nature, organisms are continuously exposed to environmental stresses that challenge their survival. The species that quickly and efficiently adapt to hostile conditions are positively selected. This response is [...]

Molecular profiling of clear cell renal cell carcinoma (ccRCC) tumors of patients in a clinical trial has identified distinct transcriptomic signatures with predictive value, yet data in non-clear cell variants (nccRCC) are lacking. We examined the transcriptional profiles of RCC tumors representing key molecular pathways, from a multi-institutional, real- world patient cohort, including ccRCC and centrally reviewed nccRCC samples. ccRCC had increased angiogenesis signature scores compared with the heterogeneous group of nccRCC tumors, while cell cycle, fatty acid oxidation/AMPK signaling, and fatty acid synthesis/pentose phosphate signature scores were increased in one or more nccRCC subtypes. Among both ccRCC and nccRCC tumors, T effector scores statistically correlated with increased immune cell infiltration and were more commonly associated with immunotherapy-related markers ([PD- L1.sup.+]/[TMB.sup.hi]/[MSI.sup.hi]). In conclusion, this study provides evidence of differential gene transcriptional profiles among ccRCC versus nccRCC tumors, providing insights for optimizing personalized and histology-specific therapeutic strategies for patients with advanced RCC., Introduction Renal cell carcinoma (RCC) is a common cancer among men and women in the United States, with an estimated 81,800 new cases and 14,890 deaths expected in 2023 (1). [...]

One critical mechanism through which prostate cancer (PCa) adapts to treatments targeting androgen receptor (AR) signaling is the emergence of ligand-binding domain-truncated and constitutively active AR splice variants, particularly AR-V7. While AR-V7 has been intensively studied, its ability to activate distinct biological functions compared with the full- length AR (AR-FL), and its role in regulating the metastatic progression of castration- resistant PCa (CRPC), remain unclear. Our study found that, under castrated conditions, AR-V7 strongly induced osteoblastic bone lesions, a response not observed with ARFL overexpression. Through combined ChIP-seq, ATAC-seq, and RNA-seq analyses, we demonstrated that AR-V7 uniquely accesses the androgen-responsive elements in compact chromatin regions, activating a distinct transcription program. This program was highly enriched for genes involved in epithelial-mesenchymal transition and metastasis. Notably, we discovered that SOX9, a critical metastasis driver gene, was a direct target and downstream effector of AR-V7. Its protein expression was dramatically upregulated in AR-V7-induced bone lesions. Moreover, we found that Ser81 phosphorylation enhanced AR-V7's pro-metastasis function by selectively altering its specific transcription program. Blocking this phosphorylation with CDK9 inhibitors impaired the AR-V7-mediated metastasis program. Overall, our study has provided molecular insights into the role of AR splice variants in driving the metastatic progression of CRPC., Introduction The androgen receptor (AR) is critical in driving prostate cancer (PCa) development, with androgen deprivation therapy (ADT) being the standard treatment for PCa patients. Although initial responses are generally [...]

* Context.--Diagnostic testing for SARS-CoV-2 in symptomatic and asymptomatic children remains integral to care, particularly for supporting return to and attendance in schools. The concordance of SARS-CoV-2 detection in children, using various specimen types, has not been widely studied. Objective.--To compare 3 sample types for SARS-CoV-2 polymerase chain reaction (PCR) testing in children, collected and tested at a single facility. Design.--We prospectively recruited 142 symptomatic and asymptomatic children/young adults into a sample comparison study performed in a single health care system. Each child provided self-collected saliva, and a trained health care provider collected a mid-turbinate nasal swab and nasopharyngeal (NP) swab. Specimens were assayed within 24 hours of collection by using reverse transcription-polymerase chain reaction (RT-PCR) to detect SARS-CoV-2 on a single testing platform. Results.--Concurrently collected saliva and mid-turbinate swabs had greater than 95% positive agreement with NP swabs when obtained within 10 days of symptom onset. Positive agreement of saliva and mid-turbinate samples collected from children with symptom onset >10 days prior, or without symptoms, was 82% compared to NP swab samples. Cycle threshold (Ct) values for mid-turbinate nasal samples more closely correlated with Ct values from NP samples than from saliva samples. Conclusions.--These findings suggest that all 3 sample types from children are useful for SARS-CoV-2 diagnostic testing by RT-PCR, and that concordance is greatest when the child has had symptoms of COVID-19 within the past 10 days. This study provides scientific justification for using sample types other than the NP swab for SARS-CoV-2 testing in pediatric populations. (Arch Pathol Lab Med. 2022;146:1056-1061; doi: 10.5858/arpa.2021-0625-SA), A pandemic provides a unique setting upon which the basic tenets of laboratory medicine are challenged. Specimen collection for SARS-CoV-2 is one such example, for which validation studies, which are [...]

A method for the quantitative determination of mRNA of TEM-type serine beta-lactamases in bacteria resistant to beta-lactam antibiotics has been developed. The method includes several stages: the isolation of a total RNA fraction from a bacterial culture and the production of the beta-lactamase target DNA in sequential reverse transcription and polymerase chain reaction with the incorporation of a biotin label, and the hybridization of the target DNA on colorimetric biochips. Sample preparation conditions were optimized to increase the yield of the analyzed target DNA. A calibration curve for determining the amount of mRNA was constructed using a standard sample of beta-lactamase TEM-1 mRNA obtained by transcription in vitro. The advantage of using a standard sample corresponding to the full-length bla.sub.TEM-1 gene is that it passes through all the stages of analysis in parallel with the test samples with the same efficiency. The detection limit for TEM-1 beta-lactamase mRNA was 0.40 ± 0.05 amol/mL; the range of determined concentrations was from 1.0 amol/mL to 2000 fmol/mL, and the relative standard deviation did not exceed 12%. The duration of analysis after the production of a bacterial culture was about 7 h. The developed method can be used to study the conditions for the expression of beta-lactamase genes in bacteria resistant to antimicrobial drugs., Author(s): M. Yu. Rubtsova [sup.1], A. A. Filippova [sup.1], N. K. Fursova [sup.2], V. G. Grigorenko [sup.1], G. V. Presnova [sup.1], M. M. Ulyashova [sup.1], A. M. Egorov [sup.1] Author [...]

Stability of the epigenetic landscape underpins maintenance of the cell-type-specific transcriptional profile. As one of the main repressive epigenetic systems, DNA methylation has been shown to be important for long-term gene silencing; its loss leads to ectopic and aberrant transcription in differentiated cells and cancer.sup.1. The developing mouse germ line endures global changes in DNA methylation in the absence of widespread transcriptional activation. Here, using an ultra-low-input native chromatin immunoprecipitation approach, we show that following DNA demethylation the gonadal primordial germ cells undergo remodelling of repressive histone modifications, resulting in a sex-specific signature in mice. We further demonstrate that Polycomb has a central role in transcriptional control in the newly hypomethylated germline genome as the genetic loss of Ezh2 leads to aberrant transcriptional activation, retrotransposon derepression and dramatic loss of developing female germ cells. This sex-specific effect of Ezh2 deletion is explained by the distinct landscape of repressive modifications observed in male and female germ cells. Overall, our study provides insight into the dynamic interplay between repressive chromatin modifications in the context of a developmental reprogramming system. Following global DNA demethylation, mouse gonadal primordial germ cells undergo remodelling of repressive chromatin modifications, resulting in a sex-specific signature that is required to safeguard the transcriptional program., Author(s): Tien-Chi Huang [sup.1] [sup.2] , Yi-Fang Wang [sup.1] , Eric Vazquez-Ferrer [sup.1] [sup.2] , Ina Theofel [sup.1] [sup.2] , Cristina E. Requena [sup.1] [sup.2] , Courtney W. Hanna [sup.3] [...]

The repair of DNA double-strand breaks (DSBs) is essential for safeguarding genome integrity. When a DSB forms, the PI3K-related ATM kinase rapidly triggers the establishment of megabase-sized, chromatin domains decorated with phosphorylated histone H2AX ([gamma]H2AX), which act as seeds for the formation of DNA-damage response foci.sup.1. It is unclear how these foci are rapidly assembled to establish a 'repair-prone' environment within the nucleus. Topologically associating domains are a key feature of 3D genome organization that compartmentalize transcription and replication, but little is known about their contribution to DNA repair processes.sup.2,3. Here we show that topologically associating domains are functional units of the DNA damage response, and are instrumental for the correct establishment of [gamma]H2AX-53BP1 chromatin domains in a manner that involves one-sided cohesin-mediated loop extrusion on both sides of the DSB. We propose a model in which H2AX-containing nucleosomes are rapidly phosphorylated as they actively pass by DSB-anchored cohesin. Our work highlights the importance of chromosome conformation in the maintenance of genome integrity and demonstrates the establishment of a chromatin modification by loop extrusion. During the repair of double-stranded DNA breaks, cohesin mediates the extrusion of loops of DNA along which phosphorylated H2AX spreads to establish a repair zone., Author(s): Coline Arnould [sup.1] , Vincent Rocher [sup.1] , Anne-Laure Finoux [sup.1] , Thomas Clouaire [sup.1] , Kevin Li [sup.2] , Felix Zhou [sup.2] , Pierre Caron [sup.1] , Philippe. [...]

The intensive application of inorganic nitrogen underlies marked increases in crop production, but imposes detrimental effects on ecosystems.sup.1,2: it is therefore crucial for future sustainable agriculture to improve the nitrogen-use efficiency of crop plants. Here we report the genetic basis of nitrogen-use efficiency associated with adaptation to local soils in rice (Oryza sativa L.). Using a panel of diverse rice germplasm collected from different ecogeographical regions, we performed a genome-wide association study on the tillering response to nitrogen--the trait that is most closely correlated with nitrogen-use efficiency in rice--and identified OsTCP19 as a modulator of this tillering response through its transcriptional response to nitrogen and its targeting to the tiller-promoting gene DWARF AND LOW-TILLERING (DLT).sup.3,4. A 29-bp insertion and/or deletion in the OsTCP19 promoter confers a differential transcriptional response and variation in the tillering response to nitrogen among rice varieties. The allele of OsTCP19 associated with a high tillering response to nitrogen is prevalent in wild rice populations, but has largely been lost in modern cultivars: this loss correlates with increased local soil nitrogen content, which suggests that it might have contributed to geographical adaptation in rice. Introgression of the allele associated with a high tillering response into modern rice cultivars boosts grain yield and nitrogen-use efficiency under low or moderate levels of nitrogen, which demonstrates substantial potential for rice breeding and the amelioration of negative environment effects by reducing the application of nitrogen to crops. OsTCP19 is a modulator of the tillering response to nitrogen in rice, and introgression of an allele of OsTCP19 associated with a high tillering response into modern rice cultivars markedly improves their nitrogen-use efficiency., Author(s): Yongqiang Liu [sup.1] [sup.2] , Hongru Wang [sup.1] , Zhimin Jiang [sup.1] , Wei Wang [sup.1] , Ruineng Xu [sup.3] [sup.4] , Qihui Wang [sup.5] , Zhihua Zhang [sup.1] [...]

Introduction Global influenza virus surveillance has been conducted through WHO Global Influenza Surveillance and Response System (GISRS) for over 65 years. (1) Currently, over 147 institutions are recognized by WHO [...]

Complex organisms can rapidly induce select genes in response to diverse environmental cues. This regulation occurs in the context of large genomes condensed by histone proteins into chromatin. The sensing of pathogens by macrophages engages conserved signalling pathways and transcription factors to coordinate the induction of inflammatory genes.sup.1-3. Enriched integration of histone H3.3, the ancestral histone H3 variant, is a general feature of dynamically regulated chromatin and transcription.sup.4-7. However, how chromatin is regulated at induced genes, and what features of H3.3 might enable rapid and high-level transcription, are unknown. The amino terminus of H3.3 contains a unique serine residue (Ser31) that is absent in 'canonical' H3.1 and H3.2. Here we show that this residue, H3.3S31, is phosphorylated (H3.3S31ph) in a stimulation-dependent manner along rapidly induced genes in mouse macrophages. This selective mark of stimulation-responsive genes directly engages the histone methyltransferase SETD2, a component of the active transcription machinery, and 'ejects' the elongation corepressor ZMYND11.sup.8,9. We propose that features of H3.3 at stimulation-induced genes, including H3.3S31ph, provide preferential access to the transcription apparatus. Our results indicate dedicated mechanisms that enable rapid transcription involving the histone variant H3.3, its phosphorylation, and both the recruitment and the ejection of chromatin regulators. The histone variant H3.3 is phosphorylated at Ser31 in induced genes, and this selective mark stimulates the histone methyltransferase SETD2 and ejects the ZMYND11 repressor, thus revealing a role for histone phosphorylation in amplifying de novo transcription., Author(s): Anja Armache [sup.1] [sup.2] , Shuang Yang [sup.3] , Alexia Martínez de Paz [sup.1] , Lexi E. Robbins [sup.1] , Ceyda Durmaz [sup.1] , Jin Q. Cheong [sup.1] , [...]

The chromatin-remodelling complex SWI/SNF is highly conserved and has critical roles in various cellular processes, including transcription and DNA-damage repair.sup.1,2. It hydrolyses ATP to remodel chromatin structure by sliding and evicting histone octamers.sup.3-8, creating DNA regions that become accessible to other essential factors. However, our mechanistic understanding of the remodelling activity is hindered by the lack of a high-resolution structure of complexes from this family. Here we report the cryo-electron microscopy structure of Saccharomyces cerevisiae SWI/SNF bound to a nucleosome, at near-atomic resolution. In the structure, the actin-related protein (Arp) module is sandwiched between the ATPase and the rest of the complex, with the Snf2 helicase-SANT associated (HSA) domain connecting all modules. The body contains an assembly scaffold composed of conserved subunits Snf12 (also known as SMARCD or BAF60), Snf5 (also known as SMARCB1, BAF47 or INI1) and an asymmetric dimer of Swi3 (also known as SMARCC, BAF155 or BAF170). Another conserved subunit, Swi1 (also known as ARID1 or BAF250), resides in the core of SWI/SNF, acting as a molecular hub. We also observed interactions between Snf5 and the histones at the acidic patch, which could serve as an anchor during active DNA translocation. Our structure enables us to map and rationalize a subset of cancer-related mutations in the human SWI/SNF complex and to propose a model for how SWI/SNF recognizes and remodels the +1 nucleosome to generate nucleosome-depleted regions during gene activation.sup.9. The cryo-electron microscopy structure of the yeast SWI/SNF complex bound to a nucleosome substrate provides insights into the chromatin-remodelling function of this family of protein complexes and suggests mechanisms by which the mutated proteins may cause cancer., Author(s): Yan Han [sup.1] , Alexis A Reyes [sup.1] [sup.2] , Sara Malik [sup.1] , Yuan He [sup.1] [sup.2] [sup.3] [sup.4] Author Affiliations: (1) Department of Molecular Biosciences, Northwestern University, [...]

Xist represents a paradigm for the function of long non-coding RNA in epigenetic regulation, although how it mediates X-chromosome inactivation (XCI) remains largely unexplained. Several proteins that bind to Xist RNA have recently been identified, including the transcriptional repressor SPEN.sup.1-3, the loss of which has been associated with deficient XCI at multiple loci.sup.2-6. Here we show in mice that SPEN is a key orchestrator of XCI in vivo and we elucidate its mechanism of action. We show that SPEN is essential for initiating gene silencing on the X chromosome in preimplantation mouse embryos and in embryonic stem cells. SPEN is dispensable for maintenance of XCI in neural progenitors, although it significantly decreases the expression of genes that escape XCI. We show that SPEN is immediately recruited to the X chromosome upon the upregulation of Xist, and is targeted to enhancers and promoters of active genes. SPEN rapidly disengages from chromatin upon gene silencing, suggesting that active transcription is required to tether SPEN to chromatin. We define the SPOC domain as a major effector of the gene-silencing function of SPEN, and show that tethering SPOC to Xist RNA is sufficient to mediate gene silencing. We identify the protein partners of SPOC, including NCoR/SMRT, the m.sup.6A RNA methylation machinery, the NuRD complex, RNA polymerase II and factors involved in the regulation of transcription initiation and elongation. We propose that SPEN acts as a molecular integrator for the initiation of XCI, bridging Xist RNA with the transcription machinery--as well as with nucleosome remodellers and histone deacetylases--at active enhancers and promoters. The transcriptional repressor SPEN bridges the non-coding RNA Xist to transcription machinery, histone deacetylases and chromatin remodelling factors to initiate X-chromosome inactivation., Author(s): François Dossin [sup.1] , Inês Pinheiro [sup.2] , Jan J. Zylicz [sup.2] [sup.3] , Julia Roensch [sup.2] , Samuel Collombet [sup.1] , Agnès Le Saux [sup.2] , Tomasz Chelmicki [...]

To acquire the eggplant transcriptome under high temperature stress, 18 cDNA libraries were constructed and sequenced. A total of 136.31 Gb of clean data was obtained, and 88.86%-92.35% of the clean reads were mapped to the eggplant reference genome. Under high temperature, the number of down-regulated genes was more than that of up-regulated genes and there were more differentially expressed genes on the 10th day after flowering than on the 15th and 20th days after flowering. On the 10th day after flowering, the key genes CHI, 3GT, F3'5'H, DFR2, ANS, and F3H in anthocyanin synthetic pathway and most ERF, WRKY, bHLH, and MYB transcription factors were all down-regulated. High temperature significantly decreased the total anthocyanin content in peels. The results showed that at the early stage of peel coloring, high temperature inhibited the expressions of key genes in anthocyanin biosynthetic pathways through the regulation of transcription factors, leading to a significant decrease in total anthocyanin content, which might reduce the peel color in eggplant. Key words: eggplant, RNA-seq, peel coloring, anthocyanin, transcription factor, high temperature stress. Afin de caracteriser le transcriptome de l'aubergine en conditions de stress thermique, 18 librairies d'ADNc ont ete preparees et sequencees. Au total, 136,31 Gb de sequences propres ont ete obtenues et 88,86-92,35% de ces sequences ont ete alignees sur le genome de reference de l'aubergine. Sous des conditions de temperature elevee, le nombre de genes moins fortement exprimes etait plus grand que celui des genes plus fortement exprimes et le nombre de genes presentant une expression differentielle etait plus eleve 10 jours apres la floraison que 15 ou 20 jours apres la floraison. Au 10 jour apres la floraison, les genes cles du sentier de synthese des anthocyanes (CHI, 3GT, F3' 5 'H, DFR2, ANS et F3H) et la plupart des facteurs de transcription des familles ERF, WRKY, bHLH et MYB etaient tous moins fortement exprimes. Une temperature elevee a reduit de maniere significative la teneur en anthocyanes totales dans la peau du fruit. Les resultats ont revele qu'aux premiers stades de coloration de la peau, une temperature elevee a inhibe l'expression des genes cles de la voie de synthese des anthocyanes via la regulation par les facteurs de transcription, menant ainsi a une diminution significative de la teneur en anthocyanes totales, laquelle pourrait reduire l'intensite de la coloration de la peau de l'aubergine. [Traduit par la Redaction] Mots-cles : aubergine, RNA-seq, coloration de la peau, anthocyanes, facteurs de transcription, stress thermique., Introduction Eggplant (Solanum melongena L.) is a thermophile vegetable and is grown throughout China. However, consumers in different regions vary preference for the shape and color of eggplant. For example, [...]

Background Salmonella enterica subsp. enterica serovar Schwarzengrund (S. Schwarzengrund) is most frequently isolated from commensals humans or poultry. Here we report S. Schwarzengrund strain S16, the first sequenced genome in the Republic of Korea. Additionally, genome sequencing for strain S16 was performed and compared with other S. Schwarzengrund genomes obtained from public database. Results Strain S16 was isolated from chicken feces. The complete genome consists of one chromosome and one plasmid. The genome size is 4,822,755 bp with 4852 coding sequences. Strain S16 was determined as serovar Schwarzengrund by in silico serotyping and typed as sequence type (ST) 96. Forty-six S. Schwarzengrund genomes yielded a pangenome of 7112 genes, core-genome of 3374 genes, accessory-genome of 2906 genes, and unique-genome of 835 genes. Eighty-one genes were unique to strain S16, including hypothetical proteins and transcriptional regulators. Genotypic analysis of antibiotic resistance of strain S16 confirmed resistance to amikacin, ciprofloxacin, sulfamethoxazole, streptomycin, and tetracycline. Unlike other S. Schwarzengrund genomes, strain S16 had a mutation of gyrB. Moreover, similar to other S. Schwarzengrund genomes reported in other countries, strain S16 was harbored for 153 virulence genes including Saf operon and cdtB gene. All the antibiotic resistance genes and virulence genes were present in the core- or accessory-genomes. Conclusions Complete genome of strain S16 was sequenced. Comparative genomic analysis revealed several genes responsible for antibiotic resistance and specific genomic features of strain S16 and identified virulence factors that might contribute to the human and animal pathogenicity of other S. Schwarzengrund genomes. Keywords: Salmonella, Schwarzengrund, Whole-genome sequencing, Comparative genomics, Antibiotic resistance gene, Virulence gene, Author(s): Seung-Min Yang[sup.1], Eiseul Kim[sup.1], Woojung Lee[sup.1] and Hae-Yeong Kim[sup.1] Background Salmonella is a major human pathogen and is the second most prevalent foodborne pathogen worldwide [1]. Salmonellosis, a disease [...]

For the initiation of transcription, RNA polymerase II (Pol II) assembles with general transcription factors on promoter DNA to form the pre-initiation complex (PIC). Here we report cryo-electron microscopy structures of the Saccharomyces cerevisiae PIC and PIC-core Mediator complex at nominal resolutions of 4.7 Å and 5.8 Å, respectively. The structures reveal transcription factor IIH (TFIIH), and suggest how the core and kinase TFIIH modules function in the opening of promoter DNA and the phosphorylation of Pol II, respectively. The TFIIH core subunit Ssl2 (a homologue of human XPB) is positioned on downstream DNA by the 'E-bridge' helix in TFIIE, consistent with TFIIE-stimulated DNA opening. The TFIIH kinase module subunit Tfb3 (MAT1 in human) anchors the kinase Kin28 (CDK7), which is mobile in the PIC but preferentially located between the Mediator hook and shoulder in the PIC-core Mediator complex. Open spaces between the Mediator head and middle modules may allow access of the kinase to its substrate, the C-terminal domain of Pol II. Cryo-electron microscopy structures of the yeast pre-initiation complex (PIC) and its complex with core Mediator provide insights into the opening of promoter DNA and the initiation of transcription. TFIIH in the transcription pre-initiation complex To initiate gene transcription, RNA polymerase (Pol) II assembles with general transcription factors on promoter DNA to form the pre-initiation complex (PIC). Here, Patrick Cramer and colleagues describe cryo-electron microscopy structures of the yeast PIC and the PIC bound to the core Mediator (cMed) complex. The latter structure with the general coactivator Mediator has 46 factors, including all those that are essential for transcription initiation in yeast. The structures reveal the architecture of transcription factor IIH (TFIIH) and suggest how its 'core' and 'kinase' modules might function in promoter opening and Pol II phosphorylation, respectively., Author(s): S. Schilbach [sup.1] , M. Hantsche [sup.1] , D. Tegunov [sup.1] , C. Dienemann [sup.1] , C. Wigge [sup.1] , H. Urlaub [sup.1] [sup.2] , P. Cramer [sup.1] Author [...]

The recognition of β cell dedifferentiation in type 2 diabetes raises the translational relevance of mechanisms that direct and maintain β cell identity. LIM domain-binding protein 1 (LDB1) nucleates multimeric transcriptional complexes and establishes promoter-enhancer looping, thereby directing fate assignment and maturation of progenitor populations. Many terminally differentiated endocrine cell types, however, remain enriched for LDB1, but its role is unknown. Here, we have demonstrated a requirement for LDB1 in maintaining the terminally differentiated status of pancreatic β cells. Inducible ablation of LDB1 in mature β cells impaired insulin secretion and glucose homeostasis. Transcriptomic analysis of LDB1-depleted β cells revealed the collapse of the terminally differentiated gene program, indicated by a loss of β cell identity genes and induction of the endocrine progenitor factor neurogenin 3 (NEUROG3). Lineage tracing confirmed that LDB1-depleted, insulin-negative β cells express NEUROG3 but do not adopt alternate endocrine cell fates. In primary mouse islets, LDB1 and its LIM homeodomain-binding partner islet 1 (ISL1) were coenriched at chromatin sites occupied by pancreatic and duodenal homeobox 1 (PDX1), NK6 homeobox 1 (NKX6.1), forkhead box A2 (FOXA2), and NK2 homeobox 2 (NKX2.2)--factors that co-occupy active enhancers in 3D chromatin domains in human islets. Indeed, LDB1 was enriched at active enhancers in human islets. Thus, LDB1 maintains the terminally differentiated state of β cells and is a component of active enhancers in both murine and human islets., Introduction All forms of diabetes are characterized by reduced numbers and/ or dysfunction of insulin-producing pancreatic islet β cells (1, 2). The β cell is unique in its ability to [...]

Triple-negative breast cancer (TNBC) includes basal-like and claudin-low subtypes for which no specific treatment is currently available. Although the retinoblastoma tumor-suppressor gene (RB1) is frequently lost together with TP53 in TNBC, it is not directly targetable. There is thus great interest in identifying vulnerabilities downstream of RB1 that can be therapeutically exploited. Here, we determined that combined inactivation of murine Rb and p53 in diverse mammary epithelial cells induced claudin-low-like TNBC with Met, Birc2/3-Mmp13-Yap1, and Pvt1-Myc amplifications. Gene set enrichment analysis revealed that Rb/p53-deficient tumors showed elevated expression of the mitochondrial protein translation (MPT) gene pathway relative to tumors harboring p53 deletion alone. Accordingly, bioinformatic, functional, and biochemical analyses showed that RB1-E2F complexes bind to MPT gene promoters to regulate transcription and control MPT. Additionally, a screen of US Food and Drug Administration-approved (FDA-approved) drugs identified the MPT antagonist tigecycline (TIG) as a potent inhibitor of Rb/p53-deficient tumor cell proliferation. TIG preferentially suppressed RB1-deficient TNBC cell proliferation, targeted both the bulk and cancer stem cell fraction, and strongly attenuated xenograft growth. It also cooperated with sulfasalazine, an FDA-approved inhibitor of cystine xCT antiporter, in culture and xenograft assays. Our results suggest that RB1 deficiency promotes cancer cell proliferation in part by enhancing mitochondrial function and identify TIG as a clinically approved drug for RB1-deficient TNBC., Introduction Breast cancer (BC) is a leading cause of cancer-related deaths in women worldwide. It can be classified into at least 5 molecular subtypes: luminal A, luminal B, human EGFR [...]

An investigation into the nuclear events involved in autophagy regulation identifies the histone arginine methyltransferase CARM1 as a transcriptional co-activator of transcription factor TFEB; CARM1 levels are decreased by the SKP2-containing E3 ubiquitin ligase and increased during autophagy induction after nutrient starvation. Autophagy induction under nutrient starvation Cells can respond to nutrient starvation with the process of autophagy, which allows cytoplasmic proteins and organelles to be degraded by the lysosome. Here, Sung Hee Baek and colleagues investigate the nuclear events involved in regulating autophagy and identify the enzyme CARM1 (co-activator-associated arginine methyltransferase 1) as a transcriptional co-activator for the autophagy transcription factor TFEB. Levels of CARM1 are repressed by a SKP2-containing E3 ubiquitin ligase SCF and are increased during autophagy induction after nutrient starvation. Autophagy is a highly conserved self-digestion process, which is essential for maintaining homeostasis and viability in response to nutrient starvation.sup.1,2,3,4. Although the components of autophagy in the cytoplasm have been well studied.sup.5,6, the molecular basis for the transcriptional and epigenetic regulation of autophagy is poorly understood. Here we identify co-activator-associated arginine methyltransferase 1 (CARM1) as a crucial component of autophagy in mammals. Notably, CARM1 stability is regulated by the SKP2-containing SCF (SKP1-cullin1-F-box protein) E3 ubiquitin ligase in the nucleus, but not in the cytoplasm, under nutrient-rich conditions. Furthermore, we show that nutrient starvation results in AMP-activated protein kinase (AMPK)-dependent phosphorylation of FOXO3a in the nucleus, which in turn transcriptionally represses SKP2. This repression leads to increased levels of CARM1 protein and subsequent increases in histone H3 Arg17 dimethylation. Genome-wide analyses reveal that CARM1 exerts transcriptional co-activator function on autophagy-related and lysosomal genes through transcription factor EB (TFEB). Our findings demonstrate that CARM1-dependent histone arginine methylation is a crucial nuclear event in autophagy, and identify a new signalling axis of AMPK-SKP2-CARM1 in the regulation of autophagy induction after nutrient starvation., Author(s): Hi-Jai R. Shin [sup.1] , Hyunkyung Kim [sup.1] , Sungryong Oh [sup.1] , Jun-Gi Lee [sup.1] , Minjung Kee [sup.1] , Hyun-Jeong Ko [sup.2] , Mi-Na Kweon [sup.3] , [...]

Autophagy is a highly conserved self-digestion process, which is essential for maintaining homeostasis and viability in response to nutrient starvation (1-4). Although the components of autophagy in the cytoplasm have been well studied (5,6), the molecular basis for the transcriptional and epigenetic regulation of autophagy is poorly understood. Here we identify co-activator-associated arginine methyltransferase 1 (CARM1) as a crucial component of autophagy in mammals. Notably, CARM1 stability is regulated by the SKP2-containing SCF (SKP1-cullin1-F-box protein) E3 ubiquitin ligase in the nucleus, but not in the cytoplasm, under nutrient-rich conditions. Furthermore, we show that nutrient starvation results in AMP-activated protein kinase (AMPK)-dependent phosphorylation of FOXO3a in the nucleus, which in turn transcriptionally represses SKP2. This repression leads to increased levels of CARM1 protein and subsequent increases in histone H3 Arg17 dimethylation. Genome-wide analyses reveal that CARM1 exerts transcriptional co-activator function on autophagy-related and lysosomal genes through transcription factor EB (TFEB). Our findings demonstrate that CARMl-dependent histone arginine methylation is a crucial nuclear event in autophagy, and identify a new signalling axis of AMPK-SKP2-CARM1 in the regulation of autophagy induction after nutrient starvation., To explore the importance of nuclear events in autophagy, we proposed that specific histone marks are involved in the epigenetic and transcriptional regulation of autophagy in the nucleus leading to [...]

Genetic variation modulates protein expression through both transcriptional and post-transcriptional mechanisms. To characterize the consequences of natural genetic diversity on the proteome, here we combine a multiplexed, mass spectrometry-based method for protein quantification with an emerging outbred mouse model containing extensive genetic variation from eight inbred founder strains. By measuring genome-wide transcript and protein expression in livers from 192 Diversity outbred mice, we identify 2,866 protein quantitative trait loci (pQTL) with twice as many local as distant genetic variants. These data support distinct transcriptional and post-transcriptional models underlying the observed pQTL effects. Using a sensitive approach to mediation analysis, we often identified a second protein or transcript as the causal mediator of distant pQTL. Our analysis reveals an extensive network of direct protein-protein interactions. Finally, we show that local genotype can provide accurate predictions of protein abundance in an independent cohort of Collaborative Cross mice., Regulation of protein abundance is vital to cellular functions and environmental response. According to the central dogma (1), the coding sequence of DNA is transcribed into mRNA (transcript), which in [...]

The general transcription factor IID (TFIID) plays a central role in the initiation of RNA polymerase II (Pol II)-dependent transcription by nucleating pre-initiation complex (PIC) assembly at the core promoter. TFIID comprises the TATA-binding protein (TBP) and 13 TBP-associated factors (TAF1-13), which specifically interact with a variety of core promoter DNA sequences. Here we present the structure of human TFIID in complex with TFIIA and core promoter DNA, determined by single-particle cryo-electron microscopy at sub-nanometre resolution. All core promoter elements are contacted by subunits of TFIID, with TAF1 and TAF2 mediating major interactions with the downstream promoter. TFIIA bridges the TBP-TATA complex with lobe B of TFIID. We also present the cryo-electron microscopy reconstruction of a fully assembled human TAF-less PIC. Superposition of common elements between the two structures provides novel insights into the general role of TFIID in promoter recognition, PIC assembly, and transcription initiation. A sub-nanometre resolution cryo-EM structure of human TFIID bound to TFIIA and core promoter DNA and a model of the TFIID-based pre-initiation complex. Promoter-bound TFIID structure This paper describes the interaction of the human general transcription factor IID (TFIID) with core promoter DNA. TFIID has a central role in the initiation of RNA polymerase II dependent transcription by nucleating assembly of the pre-initiation complex (PIC) at the promoter. Eva Nogales and colleagues determine a sub-nanometre resolution cryo-electron microscopy structure of TFIID bound to TFIIA and core promoter DNA. They also present a cryo-electron microscopy reconstruction of a fully assembled human PIC lacking TBP-associated factors (TAFs). By superimposing common elements between the TFIID-TFIIA-promoter structure and the TAF-less PIC structure, they propose a structural model for the complete TFIID-based PIC, and provide insights into the role of TFIID in promoter recognition, PIC assembly, and transcription initiation., Author(s): Robert K. Louder [sup.1] , Yuan He [sup.2] [sup.3] [sup.6] , José Ramón López-Blanco [sup.4] , Jie Fang [sup.5] , Pablo Chacón [sup.4] , Eva Nogales [sup.2] [sup.3] [sup.5] [...]

The transcription factor Foxo1 is shown to be involved in the determination of distinct subsets of regulatory T (T.sub.reg) cells, and the differentiation of activated phenotype T.sub.reg cells is associated with the repression of the Foxo1-dependent transcriptional program; constitutively active Foxo1 expression triggers depletion of activated T.sub.reg cells in peripheral tissues and leads to CD8 T-cell-mediated autoimmunity and anti-tumour immunity. Foxo1 regulation of T.sub.reg cells Ming Li and colleagues provide evidence that the transcription factor Foxo1 plays a role in the determination of distinct subsets of regulatory T (T.sub.reg) cells, and show that differentiation of activated phenotype T.sub.reg cells is associated with repression of the Foxo1-dependent transcriptional program. Constitutively active Foxo1 expression triggers depletion of T.sub.reg cells in peripheral tissues and leads to lethal CD8 T-cell-mediated autoimmunity. Tumour-infiltrating T.sub.reg cells may be more sensitive to Foxo1 gain of function. Regulatory T (T.sub.reg) cells expressing the transcription factor Foxp3 have a pivotal role in maintaining immunological self-tolerance.sup.1,2,3,4,5; yet, excessive T.sub.reg cell activities suppress anti-tumour immune responses.sup.6,7,8. Compared to the resting T.sub.reg (rT.sub.reg) cell phenotype in secondary lymphoid organs, T.sub.reg cells in non-lymphoid tissues exhibit an activated T.sub.reg (aT.sub.reg) cell phenotype.sup.9,10,11. However, the function of aT.sub.reg cells and whether their generation can be manipulated are largely unexplored. Here we show that the transcription factor Foxo1, previously demonstrated to promote T.sub.reg cell suppression of lymphoproliferative diseases.sup.12,13, has an unexpected function in inhibiting aT.sub.reg-cell-mediated immune tolerance in mice. We find that aT.sub.reg cells turned over at a slower rate than rT.sub.reg cells, but were not locally maintained in tissues. aT.sub.reg cell differentiation was associated with repression of Foxo1-dependent gene transcription, concomitant with reduced Foxo1 expression, cytoplasmic localization and enhanced phosphorylation at the Akt sites. T.sub.reg-cell-specific expression of an Akt-insensitive Foxo1 mutant prevented downregulation of lymphoid organ homing molecules, and impeded T.sub.reg cell homing to non-lymphoid organs, causing CD8.sup.+ T-cell-mediated autoimmune diseases. Compared to T.sub.reg cells from healthy tissues, tumour-infiltrating T.sub.reg cells downregulated Foxo1 target genes more substantially. Expression of the Foxo1 mutant at a lower dose was sufficient to deplete tumour-associated T.sub.reg cells, activate effector CD8.sup.+ T cells, and inhibit tumour growth without inflicting autoimmunity. Thus, Foxo1 inactivation is essential for the migration of aT.sub.reg cells that have a crucial function in suppressing CD8.sup.+ T-cell responses; and the Foxo signalling pathway in T.sub.reg cells can be titrated to break tumour immune tolerance preferentially., Author(s): Chong T. Luo [sup.1] [sup.2] , Will Liao [sup.3] , Saida Dadi [sup.1] , Ahmed Toure [sup.1] , Ming O. Li [sup.1] Author Affiliations: (1) Immunology Program, Memorial Sloan [...]

Tumour oncogenes include transcription factors that co-opt the general transcriptional machinery to sustain the oncogenic state (1), but direct pharmacological inhibition of transcription factors has so far proven difficult (2). However, the transcriptional machinery contains various enzymatic cofactors that can be targeted for the development of new therapeutic candidates (3), including cyclin-dependent kinases (CDKs) (4). Here we present the discovery and characterization of a covalent CDK7 inhibitor, THZ1, which has the unprecedented ability to target a remote cysteine residue located outside of the canonical kinase domain, providing an unanticipated means of achieving selectivity for CDK7. Cancer cell-line profiling indicates that a subset of cancer cell lines, including human T-cell acute lymphoblastic leukaemia (T-ALL), have exceptional sensitivity to THZ1. Genome-wide analysis in Jurkat T-ALL cells shows that THZ1 disproportionally affects transcription of RUNX1 and suggests that sensitivity to THZ1 may be due to vulnerability conferred by the RUNX1 super-enhancer and the key role of RUNX1 in the core transcriptional regulatory circuitry of these tumour cells. Pharmacological modulation of CDK7 kinase activity may thus provide an approach to identify and treat tumour types that are dependent on transcription for maintenance of the oncogenic state., In an effort to discover new inhibitors of kinases that regulate gene transcription, we performed cell-based screening and kinase selectivity profiling of a library of known and novel ATP-site-directed kinase [...]

In 2008, highly pathogenic avian influenza (HPAI) A(H5N1) virus became enzootic among poultry in Egypt, and the country became an epicenter for virus activity (1). As the established viruses drifted [...]

The transcription start sites used during the maternal to zygotic transition in zebrafish are mapped, revealing that the transition is characterized by a switch between two different sequence signs to guide transcription initiation, which often co-exist in core promoters. A fresh start for zygotic transcription The maternal-to-zygotic transition (MZT) during vertebrate embryogenesis represents a dramatic change of the transcriptome, when the zygotic genome is activated and maternal transcripts are degraded. This study maps the transcription start sites used during MZT in zebrafish at nucleotide resolution, and shows that the transition from maternal to zygotic transcriptome is characterized by a switch between two different promoter sequence signals. The position at which RNA transcription starts is determined by an A/T-rich motif at the maternal stage and by fundamentally different codes in the zygote. The two transcription start sites often coexist -- and may even overlap -- in core promoters and are differentially utilized at promoters active in both oocyte and embryo. A core promoter is a stretch of DNA surrounding the transcription start site (TSS) that integrates regulatory inputs.sup.1 and recruits general transcription factors to initiate transcription.sup.2. The nature and causative relationship of the DNA sequence and chromatin signals that govern the selection of most TSSs by RNA polymerase II remain unresolved. Maternal to zygotic transition represents the most marked change of the transcriptome repertoire in the vertebrate life cycle.sup.3,4,5,6. Early embryonic development in zebrafish is characterized by a series of transcriptionally silent cell cycles regulated by inherited maternal gene products: zygotic genome activation commences at the tenth cell cycle, marking the mid-blastula transition.sup.7. This transition provides a unique opportunity to study the rules of TSS selection and the hierarchy of events linking transcription initiation with key chromatin modifications. We analysed TSS usage during zebrafish early embryonic development at high resolution using cap analysis of gene expression.sup.8, and determined the positions of H3K4me3-marked promoter-associated nucleosomes.sup.9. Here we show that the transition from the maternal to zygotic transcriptome is characterized by a switch between two fundamentally different modes of defining transcription initiation, which drive the dynamic change of TSS usage and promoter shape. A maternal-specific TSS selection, which requires an A/T-rich (W-box) motif, is replaced with a zygotic TSS selection grammar characterized by broader patterns of dinucleotide enrichments, precisely aligned with the first downstream (+1) nucleosome. The developmental dynamics of the H3K4me3-marked nucleosomes reveal their DNA-sequence-associated positioning at promoters before zygotic transcription and subsequent transcription-independent adjustment to the final position downstream of the zygotic TSS. The two TSS-defining grammars coexist, often physically overlapping, in core promoters of constitutively expressed genes to enable their expression in the two regulatory environments. The dissection of overlapping core promoter determinants represents a framework for future studies of promoter structure and function across different regulatory contexts., Author(s): Vanja Haberle [sup.1] [sup.2] , Nan Li [sup.3] , Yavor Hadzhiev [sup.3] , Charles Plessy [sup.4] [sup.5] , Christopher Previti [sup.6] [sup.11] , Chirag Nepal [sup.6] [sup.11] , Jochen [...]

Novel protein-coding genes can arise either from pre-existing genes or de novo; here it is shown that functional genes emerge de novo through transitory proto-genes generated by widespread translational activity in non-genic sequences. New genes from unlikely beginnings De novo gene birth has occurred in many lineages during evolution, but how functional protein-coding genes emerge in non-functional sequences -- rather than through gene rearrangement -- remains unresolved. These authors observe in the yeast Saccharomyces cerevisiae that hundreds of species-specific non-genic transcripts are differentially regulated upon stress. These previously overlooked translation events seem to act as a reservoir of adaptive potential, in the form of open reading frames that occupy an evolutionary continuum ranging from non-genic sequences to genes. On the basis of their genome-wide observations, the authors suggest that de novo gene birth from the proto-gene reservoir may be more prevalent than sporadic gene duplication. Novel protein-coding genes can arise either through re-organization of pre-existing genes or de novo.sup.1,2. Processes involving re-organization of pre-existing genes, notably after gene duplication, have been extensively described.sup.1,2. In contrast, de novo gene birth remains poorly understood, mainly because translation of sequences devoid of genes, or 'non-genic' sequences, is expected to produce insignificant polypeptides rather than proteins with specific biological functions.sup.1,3,4,5,6. Here we formalize an evolutionary model according to which functional genes evolve de novo through transitory proto-genes.sup.4 generated by widespread translational activity in non-genic sequences. Testing this model at the genome scale in Saccharomyces cerevisiae, we detect translation of hundreds of short species-specific open reading frames (ORFs) located in non-genic sequences. These translation events seem to provide adaptive potential.sup.7, as suggested by their differential regulation upon stress and by signatures of retention by natural selection. In line with our model, we establish that S. cerevisiae ORFs can be placed within an evolutionary continuum ranging from non-genic sequences to genes. We identify ~1,900 candidate proto-genes among S. cerevisiae ORFs and find that de novo gene birth from such a reservoir may be more prevalent than sporadic gene duplication. Our work illustrates that evolution exploits seemingly dispensable sequences to generate adaptive functional innovation., Author(s): Anne-Ruxandra Carvunis [sup.1] [sup.2] [sup.3] , Thomas Rolland [sup.1] [sup.2] , Ilan Wapinski [sup.4] , Michael A. Calderwood [sup.1] [sup.2] , Muhammed A. Yildirim [sup.5] , Nicolas Simonis [sup.1] [...]

The GeneChip human mapping 250K Nsp array of affymetrix in the samples of three patients are used to perform homozygosity mapping in order to localize the missense mutated gene, MED17, segregated with disease associated with mental retardation, seizures and spasticity. The findings indicated that the p.1.371P mutation in MED17 is a founder mutation in the Caucasus Jewish community and the homozygosity in these gene mutations are associated with infantile cerebral and cerebellar atrophy with poor myelination.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2010.10.033 Byline: Liat Harel-Sharvit (1), Naama Eldad (1), Gal Haimovich (1), Oren Barkai (1), Lea Duek (1), Mordechai Choder (1) Keywords: RNA; CELLBIO Abstract: Little is known about crosstalk between the eukaryotic transcription and translation machineries that operate in different cell compartments. The yeast proteins Rpb4p and Rpb7p represent one such link as they form a heterodimer that shuttles between the nucleus, where it functions in transcription, and the cytoplasm, where it functions in the major mRNA decay pathways. Here we show that the Rpb4/7 heterodimer interacts physically and functionally with components of the translation initiation factor 3 (eIF3), and is required for efficient translation initiation. Efficient translation in the cytoplasm depends on association of Rpb4/7 with RNA polymerase II (Pol II) in the nucleus, leading to a model in which Pol II remotely controls translation. Hence, like in prokaryotes, the eukaryotic translation is coupled to transcription. We propose that Rpb4/7, through its interactions at each step in the mRNA lifecycle, represents a class of factors, 'mRNA coordinators,' which integrate the various stages of gene expression into a system. Author Affiliation: (1) Department of Molecular Microbiology, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel Article History: Received 17 December 2009; Revised 28 July 2010; Accepted 25 October 2010 Article Note: (miscellaneous) Published: November 11, 2010

Homozygosity mapping is used to identify homozygous region on chromosome 2p15 in patients with autosomal-recessive retinitis pigmentosa (arRP). The data revealed FAM161A to play significant role in photoreceptors and loss-of-function mutations in FAM161A is the major cause of arRP accounting for ~12% of arRP families in the cohort of patients from Israel and the Palestinian territories.

A combined approach of chromatic immunoprecipitation and parallel sequencing of genomic DNA was utilized to identify a gene, FAM161A which was shown to carry a homozygous nonsense mutation (p.Arg229X) in patients form the original retinitis pigmentosa 28 (RP28) pedigrees. The data obtained indicated that the RP28-associated arRP is attributed to the null mutations in FAM161A.

The DM domain proteins Doublesex- and MAB-3--related transcription factors (DMRTs) are widely conserved in metazoan sex determination and sexual differentiation. One of these proteins, DMRT1, plays diverse and essential roles in development of the vertebrate testis. In mammals DMRT1 is expressed and required in both germ cells and their supporting Sertoli cells. Despite its critical role in testicular development, little is known about how DMRT1 functions as a transcription factor or what genes it binds and regulates. We combined ChIP methods with conditional gene targeting and mRNA expression analysis and identified almost 1,400 promoter-proximal regions bound by DMRT1 in the juvenile mouse testis and determined how expression of the associated mRNAs is affected when Dmrt1 is selectively mutated in germ cells or Sertoli cells. These analyses revealed that DMRT1 is a bifunctional transcriptional regulator, activating some genes and repressing others. ChIP analysis using conditional mutant testes showed that DNA binding and transcriptional regulation of individual target genes can differ between germ cells and Sertoli cells. Genes bound by DMRT1 in vivo were enriched for a motif closely resembling the sequence DMRT1 prefers in vitro. Differential response of genes to loss of DMRT1 corresponded to differences in the enriched motif, suggesting that other transacting factors may modulate DMRT1 activity. DMRT1 bound its own promoter and those of six other Dmrt genes, indicating auto- and cross-regulation of these genes. Many of the DMRT1 target genes identified here are known to be important for a variety of functions in testicular development; the others are candidates for further investigation. chromatin immunoprecipitation | DM domain | development | transcription doi/ 10.1073/pnas.1006243107

Various DNA sequences that interfere with transcription due to their unusual structural properties have been implicated in the regulation of gene expression and with genomic instability. An important example is sequences containing G-rich homopurinehomopyrimidine stretches, for which unusual transcriptional behavior is implicated in regulation of immunogenesis and in other processes such as genomic translocations and telomere function. To elucidate the mechanism of the effect of these sequences on transcription we have studied T7 RNA polymerase transcription of G-rich sequences in vitro. We have shown that these sequences produce significant transcription blockage in an orientation-, length-and supercoiling-dependent manner. Based upon the effects of various sequence modifications, solution conditions, and ribonucleotide substitutions, we conclude that transcription blockage is due to formation of unusually stable RNA/DNA hybrids, which could be further exacerbated by triplex formation. These structures are likely responsible for transcription-dependent replication blockage by G-rich sequences in vivo. R-loops | DNA supercoiling | Hoogsteen base pairing | inosine | 7-deazaquanosine doi/ 10.1073/pnas.1007580107

A whole-genome oligonucleotide array CGH was used to identify an interstitial deletion at 8q13 in all patients with mesomelia-synostoses syndrome (MSS), a rare autosomal dominant disorder characterized by mesomelic limb shortening, acral synostoses, and multiple congenital malformations. The results obtained suggested that haploinsufficiency of SULF1 contributed significantly to the mesomelic chondrodysplasia and highlighted the critical role of endosulfatase in human skeletal development.