The 3′ processing of antisense RNAs physically links to chromatin-based transcriptional control
Xiaofeng Fang, Zhe Wu, Oleg Raitskin, Kimberly M. Webb, Philipp Voigt, Tian-Cong Lu, Martin Howard, Caroline Dean
Abstract
Significance RNA-mediated chromatin regulation is central to gene expression in many organisms. However, the mechanisms by which RNA influences the local chromatin environment are still poorly understood. Here, we show how RNA 3′ processing factors, which promote proximal polyadenylation of an Arabidopsis antisense transcript, physically associate with the chromatin modifiers FLD/LD/SDG26. The chromatin modifiers exist in a protein complex that inhibits H3K4me1 and H3K36me3 accumulation. By antagonizing transcription, the FLD/LD/SDG26-containing complex promotes H3K27me3 accumulation, reducing transcriptional initiation and elongation rates. This cotranscriptionally mediated chromatin silencing mechanism may be widely relevant for gene regulation in many organisms.