Abstract
Saccharomyces cerevisiae Ste24p is a multispanning membrane protein implicated in the CAAX proteolysis step that occurs during biogenesis of the prenylated a-factor mating pheromone. Whether Ste24p acts directly as a CAAX protease or indirectly to activate a downstream protease has not yet been established. In this study, we demonstrate that purified, detergent-solubilized Ste24p directly mediates CAAX proteolysis in a zinc-dependent manner. We also show that Ste24p mediates a separate proteolytic step, the first NH 2-terminal cleavage in a-factor maturation. These results establish that Ste24p functions both as a bona fide COOH-terminal CAAX protease and as an a-factor NH2-terminal protease. Importantly, this study is the first to directly demonstrate that a eukaryotic multispanning membrane protein can possess intrinsic proteolytic activity.
Original language | English (US) |
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Pages (from-to) | 46798-46806 |
Number of pages | 9 |
Journal | Journal of Biological Chemistry |
Volume | 276 |
Issue number | 50 |
DOIs | |
State | Published - Dec 14 2001 |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology