Argonaute2 and LaminB modulate gene expression by controlling chromatin topology (ChIP-seq)

Drosophila Argonaute2 (AGO2) is known to regulate expression of certain loci in an RNA interference-independent manner, but its genome-wide function on chromatin remains unknown. Here, we identified RNA Polymerase II (Pol II) and LaminB as AGO2 nuclear interactors. AGO2 and LaminB attenuate transcription at borders between both LaminB-associated domains (LADs) and topologically-associated domains (TADs). We identified a somatic target of AGO2 transcriptional repression, nht, which is immersed in a LAD located within a repressive TAD. Null mutation of AGO2 leads to ectopic expression of spermatogenesis genes dependent on nht. Finally, depletion of either AGO2 or LaminB results in reduced looping interactions within the TAD as well as ectopic inter-TAD interactions. Overall, our findings reveal coordination of AGO2 and LaminB to dictate overall genome architecture and thereby regulate gene expression. ChIP-seq of AGO2 in mock and LaminB knockdown, 2 replicates per experiment.