Novel Genes Involved in Endosomal Traffic in Yeast Revealed by Suppression of a Targeting-defective Plasma Membrane ATPase Mutant

• DOI: 10.1083/jcb.138.4.731
• Publication Date: 2002-07-26T16:47:50Z
• Authors: Wen-jie Luo; Amy Chang
• Keywords: 0301 basic medicine; Saccharomyces cerevisiae Proteins; Cell Membrane; Biological Transport; Nerve Tissue Proteins; Receptors, Cell Surface; Endosomes; Intracellular Membranes; Saccharomyces cerevisiae; Phosphoric Monoester Hydrolases; Fungal Proteins; Proton-Translocating ATPases; 03 medical and health sciences; Mutagenesis; Vacuoles; Proprotein Convertases; Subtilisins; Carrier Proteins; Mating Factor; Peptides; Protein Processing, Post-Translational; Biomarkers

A novel genetic selection was used to identify genes regulating traffic in the yeast endosomal system. We took advantage of a temperature-sensitive mutant PMA1, encoding plasma membrane ATPase, which newly synthesized Pma1 is mislocalized vacuole via endosome. Diversion from vacuolar delivery and rerouting major mechanism suppression pma1(ts). 16 independent suppressor pma1 (sop) mutants were isolated. Identification corresponding reveals eight that are identical with VPS required for proteins. second group SOP participates but not essential protease carboxypeptidase Y. Because biosynthetic pathway intersects endocytic pathway, internalization bulk marker FM 4-64 assayed sop mutants. By this means, defective endosome-to-vacuole trafficking revealed subset Another displays perturbed between endosome Golgi: impaired pro-alpha factor processing these strains found be due recycling trans-Golgi Kex2. One Kex2 carries mutation SOP2, homologue mammalian synaptojanin (implicated synaptic vesicle endocytosis recycling). Thus, cell surface can occur as consequence disturbances at several different sites