Title: | Ste50p sustains mating pheromone-induced signal transduction in the yeast Saccharomyces cerevisiae |
Author(s): | Xu G; Jansen G; Thomas DY; Hollenberg CP; Ramezani Rad M; |
Address: | "Institut fur Mikrobiologie, Heinrich-Heine-Universitat Dusseldorf, Germany" |
DOI: | 10.1111/j.1365-2958.1996.tb02516.x |
ISSN/ISBN: | 0950-382X (Print) 0950-382X (Linking) |
Abstract: | "In the yeast Saccharomyces cerevisiae, the heterotrimeric G protein transduces the mating pheromone signal from a cell-surface receptor. Free G beta gamma then activates a mitogen-activated protein (MAP) kinase cascade. STE50 has been shown to be involved in this pheromone signal-transduction pathway. In this study, we present a functional characterization of Ste50p, a protein that is required to sustain the pheromone-induced signal which leads cells to hormone-induced differentiation. Inactivation of STE50 leads to the attenuation of mating pheromone-induced signal transduction, and overexpression of STE50 intensifies the pheromone-induced signalling. By genetic analysis we have positioned the action of Ste50p downstream of the alpha-pheromone receptor (STE2), at the level of the heterotrimeric G protein, and upstream of STE5 and the kinase cascade of STE11 and STE7. In a two-hybrid assay Ste50p interacts weakly with the G protein and strongly with the MAPKKK Ste11p. The latter interaction is absent in the constitutive mutant Ste11pP279S. These data show that a new component, Ste50p, determines the extent and the duration of signal transduction by acting between the G protein and the MAP kinase complex in S. cerevisiae" |
Keywords: | "Alleles Fungal Proteins/*metabolism GTP-Binding Proteins/metabolism MAP Kinase Kinase Kinases/metabolism Mating Factor Peptides/*metabolism Pheromones/*metabolism Protein Serine-Threonine Kinases/metabolism Receptors, Mating Factor Receptors, Peptide/meta;" |
Notes: | "MedlineXu, G Jansen, G Thomas, D Y Hollenberg, C P Ramezani Rad, M eng Research Support, Non-U.S. Gov't England 1996/05/01 Mol Microbiol. 1996 May; 20(4):773-83. doi: 10.1111/j.1365-2958.1996.tb02516.x" |