A mutant plasma membrane ATPase, Pma1-10, is defective in stability at the yeast cell surface

• DOI: 10.1073/pnas.161282998
• Publication Date: 2002-07-26T14:37:36Z
• Authors: Xiaohua Gong; Amy Chang
• Keywords: Internalization; Cell membrane; Lipid raft

Pma1 is a plasma membrane H + -ATPase whose activity at the cell surface essential for viability. In this paper we describe temperature-sensitive pma1 allele, - 10 (with two point mutations in first cytoplasmic loop of Pma1), which newly synthesized mutant protein fails to remain stable 37°C. Instead, Pma1-10 appears undergo internalization vacuolar degradation manner dependent on End4, Vps27, Doa4, and Pep4. By contrast with wild-type Pma1, hypophosphorylated associate Triton-insoluble fraction 37°C, suggesting failure enter lipid rafts. Kinetic analysis reveals that, permissive temperature, acquires Triton-insolubility before becoming stabilized. We suggest that phosphorylation raft association may play important roles maintaining stability membrane.