The Pat1-Lsm complex prevents 3′ to 5′ degradation of a specific subset of ATG mRNAs during nitrogen starvation-induced autophagy

摘要

Deregulation of macroautophagy/autophagy, a conserved catabolic recycling pathway, has been implicated in the onset and development of several diseases. While post-translational regulation of auto-phagy-related (Atg) proteins has been an important research focus leading to significant breakthroughs in understanding autophagy regulation, less is known about the post-transcriptional regulation of transcripts. In a recent study we showed that, during nitrogen starvation, the RNA-binding complex Pat1-Lsm is involved in binding and preventing the 3ʹ to 5ʹ exosome-mediated degradation of a specific subset of mRNAs. Dephosphorylation of Pat1 at residues S456 and S457 facilitates mRNA binding, resulting in mRNA accumulation, Atg protein synthesis and robust autophagy induction. In addition, we present evidence that these processes are conserved in human cells. These results further elucidate our understanding of the post-transcriptional mechanism necessary for efficient induction of autophagy during stress conditions.