ABSTRACT: QTL mapping and marker identification for sex-determining: indicating XY sex determination system in the swimming crab (Portunus trituberculatus)
Project description:Purpose: Determine whether sex-determining genes are bivalent at the bipotential stage, poised between the testis and ovary fate, and whether H3K4me3 and H3K27me3 resolve into sex-specific patterns after sex determination, contributing to the canalization and stabilization of either the testis or ovary fate. Methods: XX and XY supporting cells of the gonad were FACS-purified before sex determination (at E10.5) and after sex determination (at E13.5), and submitted to ChIP-seq for H3K4me3, H3K27me3 and H3 as a means to normalize across cell populations. Results: We found that key sex-determining genes are bivalent at the bipotential stage. Genes that are upregulated affter sex determination are stripped of their repressive H3K27me3 mark, whereas repressed genes that promote the alternate pathway remain bivalent even after sex determination.
Project description:Mammalian gonadal sex determination is dependent on proper expression of sex determining genes in fetal gonadal somatic support cells (i.e., pre-granulosa and pre-Sertoli cells in XX and XY gonads, resp.). We used a unique transgenic mouse strain combined with microarray profiling to identify all the differentially expressed transcripts in XX and XY isolated somatic support cells during critical stages of gonadal development and differentiation.
Project description:The deletion of a single miRNA cluster, miR-17~92, is sufficient to induce primary sex reversal in XY mice. The expression of the testis determining gene, Sry, is delayed in embryonic XY miR-17~92 knockout gonads, which immediately activate the ovarian genetic program. Single cell RNA-seq analysis shows that Sertoli cell differentiation is highly reduced, delayed and unable to trigger testis differentiation. Consistent with the well-known role of miRNAs in gene regulation, the expression of target genes of miR-17~92 is not stabilized in XY mutant gonads at E11.5, affecting, in turn, the fine regulation of large gene networks involved in mammalian sex determination. Our results reveal that the miR-17~92 cluster is a novel sex-determining factor that modulates several gene networks required for accurate timing of Sry expression and Sertoli cell differentiation during testis determination and early differentiation.
Project description:The deletion of a single miRNA cluster, miR-17~92, is sufficient to induce primary sex reversal in XY mice. The expression of the testis determining gene, Sry, is delayed in embryonic XY miR-17~92 knockout gonads, which immediately activate the ovarian genetic program. Single cell RNA-seq analysis shows that Sertoli cell differentiation is highly reduced, delayed and unable to trigger testis differentiation. Consistent with the well-known role of miRNAs in gene regulation, the expression of target genes of miR-17~92 is not stabilized in XY mutant gonads at E11.5, affecting, in turn, the fine regulation of large gene networks involved in mammalian sex determination. Our results reveal that the miR-17~92 cluster is a novel sex-determining factor that modulates several gene networks required for accurate timing of Sry expression and Sertoli cell differentiation during testis determination and early differentiation. bulk RNA-seq, single cell RNA-seq as well as IF and other characterizations of a transgenic mice for miR-17~92 cluster
Project description:Mammalian gonadal sex determination is dependent on proper expression of sex determining genes in fetal gonadal somatic support cells (i.e., pre-granulosa and pre-Sertoli cells in XX and XY gonads, resp.). We used a unique transgenic mouse strain combined with microarray profiling to identify all the differentially expressed transcripts in XX and XY isolated somatic support cells during critical stages of gonadal development and differentiation. Experiment Overall Design: XX and XY somatic support cells (SSC) were isolated by flow cytometry from embryonic day (E) 11.5 and E12.5 mouse gonads. Total RNA was isolated from pools of isolated cells; 3 pools per sex and each timepoint.
Project description:Gonadal sex determining (GSD) genes that initiate fetal ovarian and testicular development and differentiation are expressed in the cells of the urogenital ridge that differentiate as somatic support cells (SSCs), i.e., granulosa cells of the ovary and Sertoli cells of the testis. To identify potential new mammalian GSD genes, we analyzed the gene expression differences between XX and XY SSCs cells isolated from the gonads of embryonic day (E) 13 mouse fetuses carrying an EGFP reporter transgene expressed specifically in SSCs. In addition, genome wide expression differences between XX and XY E13 whole gonads were examined. Newly identified differentially expressed transcripts are potential GSD genes involved in unexplained human sex reversal cases. Keywords: microarray, mouse fetal gonadal somatic support cells, sex determination