A novel cis regulatory element regulates human XIST in CTCF-dependent manner [article]

Sanjeev Galande, Rini Shah, Ashwin Kelkar
2019 bioRxiv   pre-print
The long non-coding RNA XIST is the master regulator for the process of X chromosome inactivation in mammalian females. Here we report the existence of a hitherto uncharacterized cis-regulatory element within the first exon of human XIST, which by associating with the promoter region through chromatin looping defines the transcriptional status of XIST. This interaction is brought about by CTCF, which in turn assists towards the maintenance of YY1 binding at the promoter and governs XIST
more » ... overns XIST transcription. Strikingly, the cis-element is competitively bound by pluripotency factors and CTCF, wherein the enrichment of the former disrupts its interaction with the promoter, leading to downregulation of XIST. Based on the sequence similarity of this element across species we propose that this mechanism is conserved between the human and mouse systems. Collectively, our study uncovers multiple transcription and epigenetic factors influencing XIST expression during the initiation and maintenance phases of inactivation.
doi:10.1101/871178 fatcat:nfj2ysu4vjewvgc3te22ksa2ie