Xrn1 biochemically associates to the eisosome after the post diauxic shift in yeast

Abstract

mRNA degradation is one of the main steps of gene expression, and a key player is the 5-3 exonuclease Xrn1. In Saccharomyces cerevisiae, it was previously shown, by a microscopy approach, that Xrn1 is located to different cellular compartments, depending on physiological state. During exponential growth, Xrn1 is distributed in the cytoplasm, while it is present in the eisosomes after the post-diauxic shift (PDS). Here, we biochemically characterized the Xrn1-associated complexes in different cellular states. We demonstrate that, after PDS, Xrn1 but not the decapping (DCP), nor Lsm1-7/Pat1 complexes, was sequestered in the eisosomes, thus preserving mRNAs from degradation.