Yeast mutants affecting possible quality control of plasma membrane proteins
UMass Chan Affiliations
Department of Molecular Genetics and MicrobiologyGraduate School of Biomedical Sciences
Document Type
Journal ArticlePublication Date
1999-04-17Keywords
Amino Acid Sequence; *Amino Acid Transport Systems; Amino Acid Transport Systems, Basic; Cell Membrane; Cloning, Molecular; Endosomes; Fungal Proteins; Green Fluorescent Proteins; Luminescent Proteins; Membrane Proteins; Membrane Transport Proteins; Microscopy, Fluorescence; Molecular Sequence Data; Mutation; Peptides; Protein Folding; Receptors, Cell Surface; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Sequence Homology, Amino Acid; Suppression, GeneticLife Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Mutations gef1, stp22, STP26, and STP27 in Saccharomyces cerevisiae were identified as suppressors of the temperature-sensitive alpha-factor receptor (mutation ste2-3) and arginine permease (mutation can1(ts)). These suppressors inhibited the elimination of misfolded receptors (synthesized at 34 degrees C) as well as damaged surface receptors (shifted from 22 to 34 degrees C). The stp22 mutation (allelic to vps23 [M. Babst and S. Emr, personal communication] and the STP26 mutation also caused missorting of carboxypeptidase Y, and ste2-3 was suppressed by mutations vps1, vps8, vps10, and vps28 but not by mutation vps3. In the stp22 mutant, both the mutant and the wild-type receptors (tagged with green fluorescent protein [GFP]) accumulated within an endosome-like compartment and were excluded from the vacuole. GFP-tagged Stp22p also accumulated in this compartment. Upon reaching the vacuole, cytoplasmic domains of both mutant and wild-type receptors appeared within the vacuolar lumen. Stp22p and Gef1p are similar to tumor susceptibility protein TSG101 and voltage-gated chloride channel, respectively. These results identify potential elements of plasma membrane quality control and indicate that cytoplasmic domains of membrane proteins are translocated into the vacuolar lumen.Source
Mol Cell Biol. 1999 May;19(5):3588-99.
DOI
10.1128/MCB.19.5.3588Permanent Link to this Item
http://hdl.handle.net/20.500.14038/34034PubMed ID
10207082Related Resources
ae974a485f413a2113503eed53cd6c53
10.1128/MCB.19.5.3588
Scopus Count
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