Title: | Defects in protein glycosylation cause SHO1-dependent activation of a STE12 signaling pathway in yeast |
Author(s): | Cullen PJ; Schultz J; Horecka J; Stevenson BJ; Jigami Y; Sprague GF; |
Address: | "Institute of Molecular Biology, University of Oregon, Eugene, Oregon 97403-1229, USA. gsprague@molbio.uoregon.edu" |
DOI: | 10.1093/genetics/155.3.1005 |
ISSN/ISBN: | 0016-6731 (Print) 0016-6731 (Linking) |
Abstract: | "In haploid Saccharomyces cerevisiae, mating occurs by activation of the pheromone response pathway. A genetic selection for mutants that activate this pathway uncovered a class of mutants defective in cell wall integrity. Partial loss-of-function alleles of PGI1, PMI40, PSA1, DPM1, ALG1, MNN10, SPT14, and OCH1, genes required for mannose utilization and protein glycosylation, activated a pheromone-response-pathway-dependent reporter (FUS1) in cells lacking a basal signal (ste4). Pathway activation was suppressed by the addition of mannose to hexose isomerase mutants pgi1-101 and pmi40-101, which bypassed the requirement for mannose biosynthesis in these mutants. Pathway activation was also suppressed in dpm1-101 mutants by plasmids that contained RER2 or PSA1, which produce the substrates for Dpm1. Activation of FUS1 transcription in the mannose utilization/protein glycosylation mutants required some but not all proteins from three different signaling pathways: the pheromone response, invasive growth, and HOG pathways. We specifically suggest that a Sho1 --> Ste20/Ste50 --> Ste11 --> Ste7 --> Kss1 --> Ste12 pathway is responsible for activation of FUS1 transcription in these mutants. Because loss of pheromone response pathway components leads to a synthetic growth defect in mannose utilization/protein glycosylation mutants, we suggest that the Sho1 --> Ste12 pathway contributes to maintenance of cell wall integrity in vegetative cells" |
Keywords: | Cell Wall/genetics/metabolism Fungal Proteins/genetics/*metabolism Genetic Complementation Test *Glycosylation Mannose/metabolism Membrane Glycoproteins/deficiency/genetics Membrane Proteins/metabolism Mitogen-Activated Protein Kinases/metabolism Mutation; |
Notes: | "MedlineCullen, P J Schultz, J Horecka, J Stevenson, B J Jigami, Y Sprague, G F Jr eng GM-30027/GM/NIGMS NIH HHS/ GM14591/GM/NIGMS NIH HHS/ GM19188/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 2000/07/06 Genetics. 2000 Jul; 155(3):1005-18. doi: 10.1093/genetics/155.3.1005" |