GSE174347
RNA surveillance and the periphery: a novel role for nuclear envelope protein Lem2
Transcriptionally silent chromatin often localizes at the nuclear periphery, but whether post-transcriptional gene repression also occurs at the nuclear envelope (NE) remains unknown. Here we demonstrate that the NE protein Lem2 cooperates with the nuclear exosome in RNA degradation. Loss of Lem2 causes the accumulation of non-coding RNAs and meiotic transcripts. We demonstrate that an engineered exosome RNA substrate preferentially localizes at the nuclear periphery dependent on Lem2. While Lem2 itself does not bind RNA, it physically interacts with the exosome-targeting MTREC complex and promotes the recruitment of RNAs. This Lem2-dependent pathway acts separately from nuclear bodies into which exosome factors assemble, revealing the existence of multiple degradation pathways. We propose that Lem2 recruits exosome co-factors to the nuclear periphery to coordinate RNA surveillance and fine-tunes the transcriptional program during the switch from mitotic to meiotic growth. Overall design: RNA sequencing of logaritmically growing cells