Vam10p defines a Sec18p-independent step of priming that allows yeast vacuole tethering.
نویسندگان
چکیده
YOR068c, termed VAM10 (altered vacuole morphology), lies within the VPS5 gene on the opposite DNA strand. VAM10 deletion causes vacuole fragmentation in vivo. The in vitro fusion of purified yeast vacuoles is stimulated by recombinant Vam10p and blocked by antibody to Vam10p. Vam10p acts early in the priming stage of fusion, independent of Sec18p. After priming, recombinant Vam10p will not stimulate fusion and anti-Vam10p antibodies will not inhibit; Vam10p provides a functional marker for this Sec18p-independent priming step. Pure Vam10p restores normal, Ypt7p-dependent tethering to vacuoles from a vam10Delta strain.
منابع مشابه
The docking of primed vacuoles can be reversibly arrested by excess Sec17p (alpha-SNAP).
Homotypic vacuole fusion occurs in ordered stages of priming, docking, and fusion. Priming, which prepares vacuoles for productive association, requires Sec17p (the yeast homolog of alpha-SNAP), Sec18p (the yeast NSF, an ATP-driven chaperone), and ATP. Sec17p is initially an integral part of the cis-SNARE complex together with vacuolar SNARE proteins and Sec18p (NSF). Previous studies have show...
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 100 11 شماره
صفحات -
تاریخ انتشار 2003