Silent decision: HP1 protein escorts heterochromatic RNAs to their destiny

摘要

EMBO J advance online publication June072012; doi:10.1016/j.molcel.2012.05.009 []Heterochromatin is classically perceived to be refractory to transcription because of its compact structure. However, now demonstrated that heterochromatic transcripts can accumulate even when heterochromatin is normally packaged. By tracking down the fate of these heterochromatic RNAs, they revealed a new post-transcriptional mechanism of silencing in heterochromatin that involves the dynamic turnover of HP1^Swi6 between its free, chromatin-bound and RNA-bound forms. The latter form escorts heterochromatic RNA to degradation.