CUT&Tag for GATA factors, H3K27ac and H3K27me3 in female XEN and TS cells

As the master regulator of X-chromosome inactivation (XCI), the Xist RNA is expressed nearly ubiquitously in female mice. Xist is only absent in the germ line and at the pluripotent state. Xist is generally assumed to be expressed “by default” in females, while being actively repressed in the few tissues where it is silent. Whether activating mechanisms also contribute remained largely unknown. Through a pooled CRISPR screen we identify the GATA family of transcription factors as potent direct activators of Xist. We describe a GATA-responsive regulatory element (RE79), located ~100 kb upstream of the Xist promoter. In cell lines derived from the two extraembryonic lineages, XEN and TS cells, where imprinted Xist expression is maintained, RE79 is bound by different sets of GATA factors expressed in those tissues. Here we use CUT&Tag on GATA factors to profile their involvement at the X inactivation center in XEN and TS cells. Overall design: CUT&Tag targeting GATA2, GATA3, H3K27ac and H3K27me3 was performed in a female TS cell line. CUT&Tag targeting GATA4, GATA6, H3K27ac and H3K27me3 was performed in a female XEN cell line. The data was collected in replicates.