Title: | Cdc42p GDP/GTP cycling is necessary for efficient cell fusion during yeast mating |
Author(s): | Barale S; McCusker D; Arkowitz RA; |
Address: | "Institute of Signaling, Developmental Biology, and Cancer, Centre National de la Recherche Scientifique UMR 6543, Universite de Nice, Faculte des Sciences-Parc Valrose, 06108 Nice Cedex 2, France" |
ISSN/ISBN: | 1059-1524 (Print) 1059-1524 (Linking) |
Abstract: | "The highly conserved small Rho G-protein, Cdc42p plays a critical role in cell polarity and cytoskeleton organization in all eukaryotes. In the yeast Saccharomyces cerevisiae, Cdc42p is important for cell polarity establishment, septin ring assembly, and pheromone-dependent MAP-kinase signaling during the yeast mating process. In this study, we further investigated the role of Cdc42p in the mating process by screening for specific mating defective cdc42 alleles. We have identified and characterized novel mating defective cdc42 alleles that are unaffected in vegetative cell polarity. Replacement of the Cdc42p Val36 residue with Met resulted in a specific cell fusion defect. This cdc42[V36M] mutant responded to mating pheromone but was defective in cell fusion and in localization of the cell fusion protein Fus1p, similar to a previously isolated cdc24 (cdc24-m6) mutant. Overexpression of a fast cycling Cdc42p mutant suppressed the cdc24-m6 fusion defect and conversely, overexpression of Cdc24p suppressed the cdc42[V36M] fusion defect. Taken together, our results indicate that Cdc42p GDP-GTP cycling is critical for efficient cell fusion" |
Keywords: | Amino Acid Sequence Cell Fusion Cell Polarity Genotype Guanosine Diphosphate/*metabolism Guanosine Triphosphate/*metabolism Molecular Sequence Data Mutagenesis Plasmids Saccharomyces cerevisiae/*physiology/ultrastructure Saccharomyces cerevisiae Proteins/; |
Notes: | "MedlineBarale, Sophie McCusker, Derek Arkowitz, Robert A eng Research Support, Non-U.S. Gov't 2006/03/31 Mol Biol Cell. 2006 Jun; 17(6):2824-38. doi: 10.1091/mbc.e05-11-1040. Epub 2006 Mar 29" |