Receptor-mediated protein sorting to the vacuole in yeast: Roles for a Protein Kinase, a Lipid Kinase and GTP-Binding Proteins

In this review we the structural functional characteristics of the VPS (vacuolar protein sorting) products have provided into the regulatory interactions molecular mechanisms underlying sorting pathways in eukaryotic cells. Genetic selections in yeast have in the identification of 40 for the vesicle-mediated of proteins to the lysosome-like vacuole. Molecular of VPS gene products has revealed a number of biochemical activities involved in this process. Analogous to the mannose-6-phosphate in mammalian cells, the VPS10 a transmembrane sorting receptor for the yeast vacuolar hydrolase carboxypeptidase Y. The VPS15 and VPS34 genes encode components of a novel signal transduction complex essential for the delivery of soluble vacuolar hydrolases. VPS15 and VPS34 encode a serine/ threonine protein kinase a phosphatidylinositol 3-kinase, respectively, that interact at the cytoplasmic face of an intracellular membrane compartment, most likely corresponding to the late Golgi. other VPS gene products have homologues that are involved in membrane trafficking pathways: The VPS1 and VPS21 genes encode GTPases of the dynamin rab families, respectively, and the products of the VPS33, VPS45, and PEP12/VPS6 are homologues of proteins involved in regulated synaptic vesicle exocytosis. The VPSgene products constitute components of a molecular apparatus responsible for the recognition, packaging, and vesicular transport of proteins to the vacuole in yeast.