Records of RNA localization through covalent tagging

RNA movements and localization pervade biology, from embryonic development to disease. To identify RNAs at specific subcellular locations, we anchored a uridine-adding enzyme at those sites, which then marked RNAs in its vicinity with 3 terminal uridines. RNAs were tagged independent of their translation status, and included not only mRNAs, but also ncRNAs and ncRNA processing intermediates. A battery of RNAs, including the stress sensor, IRE1, were tagged at both ER and mitochondria, and reveal RNAs whose dual localization is conserved from yeast to human cells.