The DHHC protein Pfa3 affects vacuole-associated palmitoylation of the fusion factor Vac8

Proc Natl Acad Sci U S A. 2005 Nov 29;102(48):17366-71. doi: 10.1073/pnas.0508885102. Epub 2005 Nov 21.

Abstract

Vacuole biogenesis depends on specific targeting and retention of peripheral membrane proteins. At least three palmitoylated proteins are found exclusively on yeast vacuoles: the fusion factor Vac8, the kinase Yck3, and a novel adaptor protein implicated in microautophagy, Meh1. Here, we analyze the role that putative acyltransferases of the DHHC family play in their localization and function. We find that Pfa3/Ynl326c is required for efficient localization of Vac8 to vacuoles in vivo, while Yck3 or Meh1 localization is not impaired in any of the seven DHHC deletions. Vacuole-associated Vac8 appears to be palmitoylated in a pfa3 mutant, but this population is refractive to further palmitoylation on isolated vacuoles. Vacuole morphology and inheritance, which both depend on Vac8 palmitoylation, appear normal, although there is a reduction in vacuole fusion. Interestingly, Pfa3 is required for the vacuolar localization of not only an SH4 domain that is targeted by myristate/palmitate (as in Vac8) but also one that is targeted by a myristate/basic stretch (as in Src). Our data indicate that Pfa3 has an important but not exclusive function for Vac8 localization to the vacuole.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acyltransferases / metabolism*
  • Biotinylation
  • Casein Kinase I / metabolism
  • Green Fluorescent Proteins
  • Lipoproteins / genetics
  • Lipoproteins / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Microscopy, Fluorescence
  • Mutation / genetics
  • Palmitoyl Coenzyme A / metabolism*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Vacuoles / metabolism*
  • Vesicular Transport Proteins

Substances

  • Lipoproteins
  • MEH1 protein, S cerevisiae
  • Membrane Proteins
  • Saccharomyces cerevisiae Proteins
  • VAC8 protein, S cerevisiae
  • Vesicular Transport Proteins
  • Green Fluorescent Proteins
  • Palmitoyl Coenzyme A
  • Acyltransferases
  • Pfa3 protein, S cerevisiae
  • Casein Kinase I
  • YCK3 protein, S cerevisiae