PLX055846

GSE81489: In fetal testis, SOX9 acts on transcription and splicing of its targets genes through binding to genomic regions with conserved signatures [RNA-seq]

• Organsim mouse
• Type RNASEQ
• Target gene
• Project ARCHS4

In mammals, male fate is under the control of the master transcriptional regulator, SOX9: in its presence, somatic precursor cells of the embryonic gonads differentiate into Sertoli cells, the main organizers of testicular differentiation. Therefore, analyzing target genes of this transcription factor allows understanding mechanisms of cellular commitment at the genomic level. With the use of ChIP-seq in murine and bovine wild-type testes combined with RNAseq from mouse testes lacking SOX9, we identified SOX9 target genes in the mammalian fetal gonad. SOX9 in murine and bovine fetal testes binds to a large set of genes conserved among mammals, including those with well-established roles in testis and ovary development. RNAseq analysis shows that testis and ovary display sex specific RNA splicing and that SOX9 mediates both target gene transcription and differential splicing. Regions bound by SOX9 are predominantly 5 proximal or intra-genic, and display a specific genomic features that we call "Sertoli cell signatures" or SCS. The SCS is conserved among mammals and comprises multiple binding motifs for the Sertoli reprogramming factors SOX9, GATA4 and DMRT1; indeed, independent DMRT1 ChIP-seq confirms the enrichment of the SCS. Bioinformatic analysis of SCSs regions predicts novel regulatory mechanisms prompting functional validation. For example, we detected SCS in target genes of the nuclear factor TRIM28 and we show experimentally that SOX9 and TRIM28 proteins interact in fetal testis. SOURCE: Francis Poulat (francis.poulat@igh.cnrs.fr) - IGH UPR CNRS 1142