Title: | End13p/Vps4p is required for efficient transport from early to late endosomes in Saccharomyces cerevisiae |
Author(s): | Zahn R; Stevenson BJ; Schroder-Kohne S; Zanolari B; Riezman H; Munn AL; |
Address: | "Institute of Molecular Agrobiology, National University of Singapore, Singapore, Republic of Singapore" |
ISSN/ISBN: | 0021-9533 (Print) 0021-9533 (Linking) |
Abstract: | "end13-1 was isolated in a screen for endocytosis mutants and has been shown to have a post-internalisation defect in endocytic transport as well as a defect in vacuolar protein sorting (Vps(-) phenotype), leading to secretion of newly synthesised vacuolar proteins. Here we demonstrate that END13 is identical to VPS4, encoding an AAA (ATPase associated with a variety of cellular activities)-family ATPase. We also report that the end13-1 mutation is a serine 335 to phenylalanine substitution in the AAA-ATPase domain of End13p/Vps4p. It has been reported that mutant cells lacking End13p/Vps4p (end13(vps4)Delta) accumulate endocytosed marker dyes, plasma membrane receptors and newly synthesised vacuolar hydrolase precursors in an endosomal compartment adjacent to the vacuole (prevacuolar compartment, or PVC). We find, however, that the end13 mutants have defects in transport of endocytosed fluorescent dyes, plasma membrane receptors and ligands from small peripherally located early endosomes to larger late endosomes, which are often located adjacent to the vacuole. Our results indicate that End13p/Vps4p may play an important role in multiple steps of membrane traffic through the endocytic pathway" |
Keywords: | *Adenosine Triphosphatases Endocytosis/*physiology Endosomal Sorting Complexes Required for Transport Endosomes/*metabolism Fungal Proteins/*genetics/*metabolism Mating Factor Mutagenesis/physiology Peptides/metabolism Protein Transport/physiology Sacchar; |
Notes: | "MedlineZahn, R Stevenson, B J Schroder-Kohne, S Zanolari, B Riezman, H Munn, A L eng Research Support, Non-U.S. Gov't England 2001/05/01 J Cell Sci. 2001 May; 114(Pt 10):1935-47. doi: 10.1242/jcs.114.10.1935" |