A mutant plasma membrane protein is stabilized upon loss of Yvh1, a novel ribosome assembly factor.
Pma1-10 is a mutant plasma membrane ATPase defective at the restrictive temperature in stability at the cell surface. At 37 degrees, Pma1-10 is ubiquitinated and internalized from the plasma membrane for degradation in the vacuole. YVH1, encoding a tyrosine phosphatase, is a mutant suppressor of pma1-10; in the absence of Yvh1, Pma1-10 remains stable at the plasma membrane, thereby permitting cells to grow. The RING finger domain of Yvh1, but not its phosphatase domain, is required for removal of mutant Pma1-10 from the plasma membrane. Yvh1 is a novel ribosome assembly factor: in yvh1Delta cells, free 60S and 80S ribosomal subunits are decreased, free 40S subunits are increased, and half-mer polysomes are accumulated. Pma1-10 is also stabilized by deletion of 60S ribosomal proteins Rpl19a and Rpl35a. We propose that changes in ribosome biogenesis caused by loss of Yvh1 or specific ribosomal proteins have effects on the plasma membrane, perhaps by producing specific translational changes.
Liu
Yu
Y
Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA.
Chang
Amy
A
D054637:Dual-Specificity Phosphatases / Q000737:chemistry / Q000172:deficiency* / Q000235:genetics; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism; D054683:Ribosome Subunits, Large, Eukaryotic / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D050505:Mutant Proteins; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D054637:Dual-Specificity Phosphatases; C121559:YVH1 protein, S cerevisiae; C092477:PMA1 protein, S cerevisiae; D006180:Proton-Translocating ATPases