Efficient ER exit and vacuole targeting of yeast Sna2p require two tyrosine-based sorting motifs

Henri François Renard, Didier Demaegd, Bérengère Guerriat, Pierre Morsomme

Research output: Contribution to journalArticlepeer-review


SNA (Sensitive to Na+) proteins form a membrane protein family, which, in the yeast Saccharomyces cerevisiae, is composed of four members: Sna1p/Pmp3p, Sna2p, Sna3p and Sna4p. In this study, we focused on the 79 residue Sna2p protein. We found that Sna2p is localized in the vacuolar membrane. Directed mutagenesis showed that two functional tyrosine motifs YXXØ are present in the C-terminal region. Each of these is involved in a different Golgi-to-vacuole targeting pathway: the tyrosine 65 motif is involved in adaptor protein (AP-1)-dependent targeting, whereas the tyrosine 75 motif is involved in AP-3-dependent targeting. Moreover, our data suggest that these motifs also play a crucial role in the exit of Sna2p from the endoplasmic reticulum (ER). Directed mutagenesis of these tyrosines led to a partial redirection of Sna2p to lipid bodies, probably because of a decrease in ER exit efficiency. Sna2p is the first yeast protein in which two YXXØ motifs have been identified and both were shown to be functional at two different steps of the secretory pathway, ER exit and Golgi-to-vacuole transport.

Original languageEnglish
Pages (from-to)931-946
Number of pages16
Issue number7
Publication statusPublished - 1 Jul 2010
Externally publishedYes


  • Lipid bodies
  • Secretory pathway
  • Vacuole
  • Yeast
  • YXXØ motif


Dive into the research topics of 'Efficient ER exit and vacuole targeting of yeast Sna2p require two tyrosine-based sorting motifs'. Together they form a unique fingerprint.

Cite this