Title: | Cis- and trans-acting functions required for endocytosis of the yeast pheromone receptors |
Author(s): | Davis NG; Horecka JL; Sprague GF; |
Address: | "Institute of Molecular Biology, University of Oregon, Eugene 97403" |
ISSN/ISBN: | 0021-9525 (Print) 1540-8140 (Electronic) 0021-9525 (Linking) |
Abstract: | "The Saccharomyces cerevisiae a-factor receptor (STE3) is subject to two modes of endocytosis: a constitutive process that occurs in the absence of ligand and a regulated process that is triggered by binding of ligand. Both processes result in delivery of the receptor to the vacuole for degradation. Receptor mutants deleted for part of the COOH-terminal cytoplasmic domain are disabled for constitutive, but not ligand-dependent internalization. Trans-acting mutants that impair constitutive endocytosis have been isolated. One of these, ren1-1, is blocked at a late step in the endocytic pathway, as receptor accumulates in a prevacuolar endosome-like compartment. REN1 is identical to VPS2, a gene required for delivery of newly synthesized vacuolar enzymes to the vacuole. Based on this identity, we suggest a model in which the transport pathways to the vacuole--the endocytic pathway and the vacuolar biogenesis pathway--merge at an intermediate endocytic compartment. As receptor also accumulates at the surface of ren1 cells, receptor may recycle from the putative endosome to the surface, or REN1 may also be required to carry out an early step in endocytosis" |
Keywords: | "Crosses, Genetic Endocytosis GTP-Binding Proteins/metabolism Genes, Fungal Genes, myc Genotype Mutagenesis Receptors, Cell Surface/genetics/*metabolism *Receptors, G-Protein-Coupled Receptors, Mating Factor *Receptors, Peptide *Receptors, Pheromone Saccha;" |
Notes: | "MedlineDavis, N G Horecka, J L Sprague, G F Jr eng GM 30027/GM/NIGMS NIH HHS/ GM 38157/GM/NIGMS NIH HHS/ GM1 12672/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 1993/07/01 J Cell Biol. 1993 Jul; 122(1):53-65. doi: 10.1083/jcb.122.1.53" |