Project description:A major event in mammalian male sex determination is the induction of the testis determining factor Sry and its downstream gene Sox9. The current study provides one of the first genome wide analyses of the downstream gene binding targets for SRY and SOX9 to help elucidate the molecular control of Sertoli cell differentiation and testis development. A modified ChIP-Chip analysis using a comparative hybridization was used to identify 71 direct downstream binding targets for SRY and 109 binding targets for SOX9. Interestingly, only 5 gene targets overlapped between SRY and SOX9. In addition to the direct response element binding gene targets, a large number of atypical binding gene targets were identified for both SRY and SOX9. Bioinformatic analysis of the downstream binding targets identified gene networks and cellular pathways potentially involved in the induction of Sertoli cell differentiation and testis development. The specific DNA sequence binding site motifs for both SRY and SOX9 were identified. Observations provide insights into the molecular control of male gonadal sex determination. The current study provides one of the first genome wide analyses of the downstream gene binding targets for SRY and SOX9 to help elucidate the molecular control of Sertoli cell differentiation and testis development. At embryonic day 13 (E13) of pregnancy rats were euthanized and embryonic gonads were collected for chromatin. A modified ChIP-Chip analysis using a comparative hybridization was used to identify direct downstream binding targets for SRY and for SOX9. Then, bioinformatic analysis of the downstream binding targets was done to identify gene networks and cellular pathways that are potentially involved in the induction of Sertoli cell differentiation and testis development.
Project description:A major event in mammalian male sex determination is the induction of the testis determining factor Sry and its downstream gene Sox9. The current study provides one of the first genome wide analyses of the downstream gene binding targets for SRY and SOX9 to help elucidate the molecular control of Sertoli cell differentiation and testis development. A modified ChIP-Chip analysis using a comparative hybridization was used to identify 71 direct downstream binding targets for SRY and 109 binding targets for SOX9. Interestingly, only 5 gene targets overlapped between SRY and SOX9. In addition to the direct response element binding gene targets, a large number of atypical binding gene targets were identified for both SRY and SOX9. Bioinformatic analysis of the downstream binding targets identified gene networks and cellular pathways potentially involved in the induction of Sertoli cell differentiation and testis development. The specific DNA sequence binding site motifs for both SRY and SOX9 were identified. Observations provide insights into the molecular control of male gonadal sex determination. The current study provides one of the first genome wide analyses of the downstream gene binding targets for SRY and SOX9 to help elucidate the molecular control of Sertoli cell differentiation and testis development. At embryonic day 13 (E13) of pregnancy rats were euthanized and embryonic gonads were collected for chromatin. A modified ChIP-Chip analysis using a comparative hybridization was used to identify direct downstream binding targets for SRY and for SOX9. Then, bioinformatic analysis of the downstream binding targets was done to identify gene networks and cellular pathways that are potentially involved in the induction of Sertoli cell differentiation and testis development.
Project description:A critical transcription factor required for mammalian male sex determination is SRY (sex determining region on the Y chromosome). The expression of SRY in precursor Sertoli cells is one of the initial events in testis development. The current study was designed to determine the impact of environmentally induced epigenetic transgenerational inheritance on SRY during gonadal sex determination in the male. The agricultural fungicide vinclozolin and vehicle control (DMSO) exposed gestating females (F0 generation) during gonadal sex determination promoted the transgenerational inheritance of differential DNA methylation in sperm of the F3 generation (great grand-offspring). The fetal gonads in F3 generation males were used to identify potential alterations in SRY binding sites in the developing Sertoli cells. Chromatin immunoprecipitation with an SRY antibody followed by genome-wide promoter tiling array (ChIP-Chip) was used to identify alterations in SRY binding. A total of 81 adjacent oligonucleotide sites and 173 single oligo SRY binding sites were identified to be altered transgenerationally in the Sertoli cell vinclozolin lineage F3 generation males. Observations demonstrate the majority of the previously identified normal SRY binding sites were not altered and the altered SRY binding sites were novel and new additional sites. The chromosomal locations, gene associations and potentially modified cellular pathways were investigated. In summary, environmentally induces epigenetic transgenerational inheritance of germline epimutations appears to alter the cellular differentiation and development of the precursor Sertoli cell SRY binding during gonadal sex determination that influence the developmental origins of adult onset testis disease. The experimental design involved the intraperitoneal exposure of gestating female rats to vinclozolin or a vehicle control (dimethyl sulfoxide, DMSO) transiently from embryonic days E8-E14. Sister littermates were divided into control and vinclozolin treatment groups and mated to similar males to minimize the genetic variation between the control and vinclozolin lineages. Sufficient females were used so no inbreeding (sibling or cousin) occurred in any generation. The F1 generation was bred within the lineage to generate the F2 generation and these F2 generation bred to generate the F3 generation. The only exposure was the F0 generation female. The F3 generation control and vinclozolin lineage embryonic day 13 (E13) embryos were collected and the gonads micro-dissected and then sexed with an SRY PCR protocol. The male gonads were pooled from a minimum of three different litters and the pools used to collect DNA. Three different experiments were performed to collect 3 control and vinclozolin E13 F3 generation testis pools, each with different animals (n=25 gonads/pool). The chromatin DNA (not denatured) from each pool was fragmented and used in an SRY chromatin immunoprecipitation (ChIP) procedure for each pool separately. The control and vinclozolin SRY ChIP DNA were paired for a competitive hybridization on a genome-wide promoter tiling array (ChIP-Chip) assay. The hybridization data obtained was used to identify the SRY binding sites that were different in the F3 generation vinclozolin versus control lineage in E13 testis.
Project description:A number of environmental factors (e.g. toxicants) have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. Transgenerational inheritance requires the germline transmission of altered epigenetic information between generations in the absence of direct environmental exposures. The primary periods for epigenetic programming of the germline is associated with primordial germ cell development and during fetal gonadal sex determination. The current study examined the actions of an agricultural fungicide vinclozolin on gestating female (F0 generation) progeny in regards to the primordial germ cell (PGC) epigenetic reprogramming of the F3 generation (i.e. great-grandchildren). The F3 generation primordial germ cell transcriptome and epigenome (DNA methylation) was altered transgenerationally. Interestingly, the differential DNA methylation regions (DMR) and altered transcriptomes were distinct between the onset of gonadal sex determination at embryonic day 13 (E13) and after cord formation in the testis at embryonic day 16 (E16). A larger number of DMR and transcriptional alterations were observed in the E13 PGC than E16 germ cells. Observations demonstrate an altered transgenerational epigenetic reprogramming and function of the primordial germ cells and subsequent male germline is a component of vinclozolin induced epigenetic transgenerational inheritance of disease. Insights into the molecular control of germline transmitted epigenetic inheritance are provided. The combined observations demonstrate ancestral exposure of a gestating female during fetal gonadal sex determination can promote transgenerational alterations in the primordial germ cell and subsequent male germline epigenetic and transcriptional programming. This altered germline programming leads to the epigenetic transgenerational inheritance of disease and phenotypic variation. Observations support the role of the primordial germ cell programming in the molecular mechanism involved and provides insights into the molecular mechanisms that control the epigenetic transgenerational inheritance phenomena. Results suggest a cascade of epigenetic and transcriptional events during germ cell development is needed to obtain the mature germline epigenome that is then transmitted transgenerationally. RNA samples from PGC of 2 F3-control lineage groups were compared to PGC of 2 F3-vinclozolin lineage groups for two embryonic age E13 and E16
Project description:Definition of genome wide binding profile of Olig2, Ascl1, Tcf3, Max, NFI, Sox2, Sox9 and Sox21 in mouse neural stem cells.<br><br>Three sets of processed data files, together with a README file (README_E-MTAB-2228.docx) describing the source and content of each file, are provided as additional files to this ArrayExpress submission and can be found in https://www.ebi.ac.uk/arrayexpress/files/E-MTAB-2228 .
Project description:We report here the genome-wide localization of the histone acetyltransferase MYST5 (cg1984) in Drosophila. ChIP-seq analysis was performed with two anti-MYST5 antibodies in S2 cells. We found MYST5 to bind to the promoters of actively transcribed genes. MYST5 furthermore showed extensive colocalization with boundary/ insulator factors, including Chriz/ Chromator, CP190, dCTCF and BEAF-32, which mediate the organization of the genome into functionally distinct topological domains. Altogether, our data suggest a broad role for MYST5 both in gene-specific transcriptional regulation and in the organization of the genome into chromatin domains. Examination of genome-wide MYST5 localization in S2 cells
Project description:Transcription factors (TFs) do not function alone but work together with other TFs (called co-TFs) in a combinatorial fashion to precisely control the transcription of target genes. Mining co-TFs is thus important to understand the mechanism of transcriptional regulation. Although existing methods can identify co-TFs, their accuracy depends heavily on the chosen background model and other parameters such as the enrichment window size and the PWM score cut-off. In this study, we have developed a novel web-based co-motif scanning program called CENTDIST (http://compbio.ddns.comp.nus.edu.sg/~chipseq/centdist/). In comparison to current co-motif scanning programs, CENTDIST does not require the input of any user-specific parameters and background information. Instead, CENTDIST automatically determines the best set of parameters and ranks co-TF motifs based on their distribution around ChIP-seq peaks. We tested CENTDIST on 14 ChIP-seq datasets and found CENTDIST is more accurate than existing methods. In particular, we applied CENTDIST on an Androgen Receptor (AR) ChIP-seq dataset from a prostate cancer cell line and correctly predicted all known co-TFs (8 TFs) of AR in the top 20 hits as well as discovering AP4 as a novel co-TF of AR (which was missed by existing methods). Taken together, CENTDIST, which exploits the imbalanced nature of co-TF binding, is a user-friendly, parameter-less, and powerful predictive web-based program for understanding the mechanism of transcriptional co-regulation. Genome-wide binding analyses of AP4 in LNCaP with DHT (5alpha-dihydrotestosterone) stimulation using ChIP-Seq.
Project description:Androgen receptor (AR) orchestrates an intricate transcriptional regulatory network that governs prostate cancer initiation, development and progression. To understand this network in detail, we generated genome-wide maps of AR occupancy by ChIP-seq in LNCaP cells. We found NKX3-1, an androgen-dependent homeobox protein well-characterized for its role in prostate development and differentiation, being recruited to AR binding sites (ARBS) in response to androgen signaling. We identified 6,359 NKX3-1 binding sites, most of which overlapped with AR. In addition to its novel collaborative transcriptional role at well-known prostate cancer model genes, our binding and knockdown studies further suggested that NKX3-1 potentially regulates AR in a feed-forward manner. Integrative analysis of Oncomine molecular concepts showed that these androgen-regulated AR and NKX3-1 associated genes are significantly overexpressed in prostate carcinoma as well as advanced and recurrent prostate tumors. From our transcriptomic profiling and Gene Ontology analysis, we observed that AR and NKX3-1 co-regulate genes involved in "protein trafficking" processes, which are mandatory events in the integration of oncogenic signaling pathways leading to prostate cancer development and progression. Interestingly, we found that AR and NKX3-1 co-regulate several members of the RAB GTPase family of secretory/trafficking proteins via the involvement of FoxA1 in a ternary complex and we believe that these AR/NKX3-1/FoxA1 co-regulated RAB genes could serve as expression signatures in prostate carcinogenesis. More specifically, through functional analyses, we showed that NKX3-1, together with AR and FoxA1, could promote prostate cancer cell survival through activation of RAB3B expression. Collectively, our study has provided important insights into the hierarchical transcriptional regulatory network established between AR and NKX3-1 and sought to elucidate the important genetic-molecular-phenotypic paradigm in androgen-dependent prostate cancer. Genome-wide binding analyses of AR, NKX3-1 and FoxA1 in LNCaP with or without DHT (5alpha-dihydrotestosterone) stimulation using ChIP-Seq.
Project description:The Goto-Kakizak (GK) rat, a nonobese animal model of Type 2 diabetes (T2D), were developed by repeated inbreeding of glucose-intolerent individuals selected from Wistar rats. During their development, GK rats suffer from reduced beta-cell mass and insulin resistance spontaneously (T2D phenotype), which are supposed to be caused by loci holding different genotypes between GK and Wistar rats. This array CGH experiment can detect loci which show different copy numbers (genotype) between GK and Wistar rats. These loci serve as a valuable repository for mining candidates contributing to the pathogenesis of T2D. The genomic DNA taken from 3 male GK rats as 3 test samples while pooled genomic DNA from 8 male Wistar rats as the common referrence. For each of the hybridization, a dye-swap was designed as well.
Project description:Aluminum (Al) toxicity, which is caused by the solubilization of Al3 in acid soils resulting in inhibition of root growth and nutrient/water acquisition, is a serious limitation to crop production, because up to one-half of the world?s potentially arable land is acidic. To date, however, no Al tolerance genes have yet been cloned. The physiological mechanisms of tolerance are somewhat better understood; the major documented mechanism involves the Al-activated release of Al-binding organic acids from the root tip, preventing uptake into the primary site of toxicity. In this study, a quantitative trait loci analysis of Al tolerance in Arabidopsis was conducted, which also correlated Al tolerance quantitative trait locus (QTL) with physiological mechanisms of tolerance. The analysis identified two major loci, which explain approximately 40% of the variance in Al tolerance observed among recombinant inbred lines derived from Landsberg erecta (sensitive) and Columbia (tolerant). We characterized the mechanism by which tolerance is achieved, and we found that the two QTL cosegregate with an Al-activated release of malate from Arabidopsis roots. Although only two of the QTL have been identified, malate release explains nearly all (95%) of the variation in Al tolerance in this population. Al tolerance in Landsberg erecta Columbia is more complex genetically than physiologically, in that a number of genes underlie a single physiological mechanism involving root malate release. These findings have set the stage for the subsequent cloning of the genes responsible for the Al tolerance QTL, and a genomics-based cloning strategy and initial progress on this are also discussed. A replicate experimental design type is where a series of replicates are performed to evaluate reproducibility or as a pilot study to determine the appropriate number of replicates for a subsequent experiments. Computed