|Protein sorting in yeast: mutants defective in vacuole biogenesis mislocalize vacuolar proteins into the late secretory pathway.
|Year of Publication
|Rothman JH, Stevens TH
|1986 Dec 26
|alpha-Mannosidase, Aspartic Acid Endopeptidases, beta-Fructofuranosidase, Carboxypeptidases, Cathepsin A, Endopeptidases, Fungal Proteins, Genes, Fungal, Glycoside Hydrolases, Mannosidases, Microscopy, Electron, Mutation, Organoids, Phenotype, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Serine Endopeptidases, Vacuoles
We have devised a genetic selection for mutant yeast cells that fail to properly deliver the vacuolar glycoprotein CPY to the lysosome-like vacuole. This has allowed us to identify mutations in eight VPL complementation groups that result in aberrant secretion of up to approximately 90% of the immunoreactive CPY. Other soluble vacuolar proteins are also affected by each vpl mutation, demonstrating that a sorting system for multiple vacuolar proteins exists in yeast. Mislocalized CPY apparently traverses late stages of the secretory pathway, since a vesicle-accumulating sec1 mutation prevents secretion of this protein. Despite the presence of abnormal membrane-enclosed organelles in some of the vpl mutants, maturation and secretion of invertase are not substantially perturbed. Thus vpl mutations define a new class of genes that encode products required for sorting of newly synthesized vacuolar proteins from secretory proteins during their transit through the yeast secretory pathway.
|GM 32448 / GM / NIGMS NIH HHS / United States