Palmitoylation plays a role in targeting Vac8p to specific membrane subdomains.
Vac8p is a multifunctional yeast protein involved in several distinct vacuolar events including vacuole inheritance, vacuole homotypic fusion, nucleus-vacuole junction formation and the cytoplasm to vacuole protein targeting pathway. Vac8p associates with the vacuole membrane via myristoylation and palmitoylation. Vac8p has three putative palmitoylation sites, at Cys 4, 5 and 7. Here, we show that each of these cysteines may serve as a palmitoylation site. Palmitoylation at Cys 7 alone provides partial function of Vac8p, whereas palmitoylation at either Cys 4 or Cys 5 alone is sufficient for Vac8p function. In the former mutant, there is a severe defect in the localization of Vac8p to the vacuole membrane, while in the latter mutants, there is a partial defect in the localization of Vac8p. In addition, our studies provide evidence that palmitoylation targets Vac8p to specific membrane subdomains.
Peng
Yutian
Y
Department of Cell & Developmental Biology, Life Sciences Institute, 210 Washtenaw Avenue, Room 6437, University of Michigan, Ann Arbor, MI 48109-2216, USA.
Tang
Fusheng
F
Weisman
Lois S
LS
D000595:Amino Acid Sequence; D002110:Caffeine / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism* / Q000648:ultrastructure; D002467:Cell Nucleus / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism; D025141:Drug Resistance, Fungal; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D008074:Lipoproteins / Q000235:genetics / Q000378:metabolism*; D021962:Membrane Microdomains; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D014617:Vacuoles / Q000378:metabolism* / Q000648:ultrastructure; D033921:Vesicular Transport Proteins
D005656:Fungal Proteins; D008074:Lipoproteins; D008565:Membrane Proteins; D010726:Phosphodiesterase Inhibitors; D029701:Saccharomyces cerevisiae Proteins; C111373:VAC8 protein, S cerevisiae; D033921:Vesicular Transport Proteins; D002110:Caffeine; D003545:Cysteine