Genome-Wide Yan Chromatin Occupancy in Drosophila Embryos

The ETS transcriptional repressor Yan functions as part of a developmental switch that in response to receptor tyrosine kinase signaling, transitions from a high-Yan to a low-Yan state to direct specification of a variety of cell fates. To date very few direct target genes have been identified, nor is it clear how their expression is buffered against developmental noise to prevent inappropriate oscillations between states. Following investigation of its genome-wide chromatin occupancy profile, we noticed a striking signature at developmentally important genes whereby Yan associates with chromatin in regions of high-peak density that span multiple kilobases which partially relies upon SAM-domain mediated self-association. We speculate that the high-density Yan occupancy signature may reveal a novel mechanism that buffers the expression of critical developmental regulators against intrinsic and environmental noise. The supplementary bed file contains Yan binding regions. Yan ChIP from staged Drosophila embryos