Evolutionarily conserved 5'-3' exoribonuclease Xrn1 accumulates at plasma membrane-associated eisosomes in post-diauxic yeast

PLoS One. 2015 Mar 26;10(3):e0122770. doi: 10.1371/journal.pone.0122770. eCollection 2015.

Abstract

Regulation of gene expression on the level of translation and mRNA turnover is widely conserved evolutionarily. We have found that the main mRNA decay enzyme, exoribonuclease Xrn1, accumulates at the plasma membrane-associated eisosomes after glucose exhaustion in a culture of the yeast S. cerevisiae. Eisosomal localization of Xrn1 is not achieved in cells lacking the main component of eisosomes, Pil1, or Sur7, the protein accumulating at the membrane compartment of Can1 (MCC) - the eisosome-organized plasma membrane microdomain. In contrast to the conditions of diauxic shift, when Xrn1 accumulates in processing bodies (P-bodies), or acute heat stress, in which these cytosolic accumulations of Xrn1 associate with eIF3a/Rpg1-containing stress granules, Xrn1 is not accompanied by other mRNA-decay machinery components when it accumulates at eisosomes in post-diauxic cells. It is important that Xrn1 is released from eisosomes after addition of fermentable substrate. We suggest that this spatial segregation of Xrn1 from the rest of the mRNA-decay machinery reflects a general regulatory mechanism, in which the key enzyme is kept separate from the rest of mRNA decay factors in resting cells but ready for immediate use when fermentable nutrients emerge and appropriate metabolism reprogramming is required. In particular, the localization of Xrn1 to the eisosome, together with previously published data, accents the relevance of this plasma membrane-associated compartment as a multipotent regulatory site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Membrane / genetics
  • Cell Membrane / metabolism*
  • Exoribonucleases / genetics
  • Exoribonucleases / metabolism*
  • Gene Expression
  • Genes, Reporter
  • Glucose / metabolism
  • Heat-Shock Response
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • Exoribonucleases
  • XRN1 protein, S cerevisiae
  • Glucose

Grants and funding

This work was financially supported by the Czech Science Foundation (projects P302/11/0146 and 15-10641S to M.O., V.S. and J.M.; P304/12/0480 to T.G. and J. H.) and by the institutional grants. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.