Title: | The yeast multidrug transporter Pdr5 of the plasma membrane is ubiquitinated prior to endocytosis and degradation in the vacuole |
Address: | "Department of Molecular Genetics, University and Biocenter Vienna, Austria" |
DOI: | 10.1016/0014-5793(95)01450-0 |
ISSN/ISBN: | 0014-5793 (Print) 0014-5793 (Linking) |
Abstract: | "We have recently demonstrated that the Pdr5 ATP binding cassette multidrug transporter is a short-lived protein, whose biogenesis involves cell surface targeting followed by endocytosis and delivery to the vacuole for proteolytic turnover [Egner, R., Mahe, Y., Pandjaitan, R., and Kuchler, K. (1995) Mol. Cell. Biol. 15, 5879-5887]. Using c-myc epitope-tagged ubiquitin, we now have shown that Pdr5 is a ubiquitinated plasma membrane protein in vivo. Ubiquitination of Pdr5 was detected in both wild type and conditional end mutants defective in endocytic vesicle formation. Likewise, the Ste6 a-factor pheromone transporter, which represents another short-lived ABC transporter whose turnover requires vacuolar proteolysis, was also found to be ubiquitinated, and ubiquitin-modified Ste6 massively accumulated in end4 mutants at the restrictive temperature. By contrast, the plasma membrane ATPase Pma1, a long-lived and metabolically very stable protein, was found not to be ubiquitinated. Our results imply a novel function for ubiquitin in protein trafficking and suggest that ubiquitination of certain short-lived plasma membrane proteins may trigger their endocytic delivery to the vacuole for proteolytic turnover" |
Keywords: | ATP-Binding Cassette Transporters/*metabolism Cell Membrane/chemistry *Endocytosis Fungal Proteins/*metabolism Hemagglutinins Membrane Proteins/*metabolism Saccharomyces cerevisiae/*chemistry *Saccharomyces cerevisiae Proteins Ubiquitins/*metabolism Vacuo; |
Notes: | "MedlineEgner, R Kuchler, K eng Research Support, Non-U.S. Gov't England 1996/01/08 FEBS Lett. 1996 Jan 8; 378(2):177-81. doi: 10.1016/0014-5793(95)01450-0" |