Regulation of Ras Localization and Cell Transformation by Evolutionarily Conserved Palmitoyltransferases

Mol Cell Biol. 2014 Feb;34(3):374-85. doi: 10.1128/MCB.01248-13. Epub 2013 Nov 18.

Abstract

Ras can act on the plasma membrane (PM) to mediate extracellular signaling and tumorigenesis. To identify key components controlling Ras PM localization, we performed an unbiased screen to seek Schizosaccharomyces pombe mutants with reduced PM Ras. Five mutants were found with mutations affecting the same gene, S. pombe erf2 (sp-erf2), encoding sp-Erf2, a palmitoyltransferase, with various activities. sp-Erf2 localizes to the trans-Golgi compartment, a process which is mediated by its third transmembrane domain and the Erf4 cofactor. In fission yeast, the human ortholog zDHHC9 rescues the phenotypes of sp-erf2 null cells. In contrast, expressing zDHHC14, another sp-Erf2-like human protein, did not rescue Ras1 mislocalization in these cells. Importantly, ZDHHC9 is widely overexpressed in cancers. Overexpressing ZDHHC9 promotes, while repressing it diminishes, Ras PM localization and transformation of mammalian cells. These data strongly demonstrate that sp-Erf2/zDHHC9 palmitoylates Ras proteins in a highly selective manner in the trans-Golgi compartment to facilitate PM targeting via the trans-Golgi network, a role that is most certainly critical for Ras-driven tumorigenesis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acyltransferases / genetics
  • Acyltransferases / metabolism*
  • Animals
  • Blotting, Western
  • Cell Line
  • Cell Line, Tumor
  • Cell Membrane / metabolism*
  • Cell Transformation, Neoplastic*
  • Conserved Sequence / genetics
  • Evolution, Molecular
  • Genetic Complementation Test
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • HEK293 Cells
  • Humans
  • Mice
  • Microscopy, Confocal
  • Mutation
  • NIH 3T3 Cells
  • Palmitic Acids / metabolism
  • Schizosaccharomyces / enzymology
  • Schizosaccharomyces / genetics
  • Schizosaccharomyces / metabolism
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism*
  • ras Proteins / genetics
  • ras Proteins / metabolism*
  • trans-Golgi Network / metabolism

Substances

  • Palmitic Acids
  • Schizosaccharomyces pombe Proteins
  • Green Fluorescent Proteins
  • Acyltransferases
  • Erf2 protein, S pombe
  • ZDHHC9 protein, human
  • Ras1 protein, S pombe
  • ras Proteins