Alternative polyadenylation regulates mitochondrial sod2 during yeast quiescence transitions

In a new preprint, researchers mapped alternative polyadenylation dynamics across 15 time points of quiescence transitions in fission yeast. Using 3'-end RNA sequencing, the team tracked post-transcriptional remodeling as cells entered, maintained, and exited quiescence. They observed global 3' untranslated region lengthening during early entry, shortening upon quiescence establishment, and a return to baseline lengths during quiescence exit. By pairing these dynamics with expression analysis, they found that the mitochondrial superoxide dismutase gene sod2 autoregulates its mRNA and protein levels through alternative polyadenylation. Disrupting the proximal polyadenylation site of sod2 in a mitophagy-deficient background worsened mitochondrial dysfunction and quiescence maintenance defects. The authors further identified Pabp as an upstream regulator driving this sod2 control axis.