Vacuole acidification is required for trans-SNARE pairing, LMA1 release, and homotypic fusion

被引：92

作者：

Ungermann, C ^{[1
]}

Wickner, W ^{[1
]}

Xu, ZY ^{[1
]}

机构：

[1] Dartmouth Med Sch, Dept Biochem, Hanover, NH 03755 USA

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 1999年 / 96卷 / 20期

关键词：

D O I：

10.1073/pnas.96.20.11194

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Vacuole fusion occurs in three stages: priming, in which Sec18p mediates Sec17p release, LMA1 (low M-r activity 1) relocation, and cis-SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complex disassembly; docking, mediated by Ypt7p and trans-SNARE association; and fusion of docked vacuoles. Ca2+ and calmodulin regulate late stages of the reaction. We now show that the vacuole proton gradient, generated by the vacuolar proton ATPase, is needed for trans-SNARE complex formation during docking and hence for the subsequent LMA1 release. Though neither the vacuolar Pmc1p Ca2+-ATPase nor the Vcx1p Ca2+/H+ exchanger are needed for the fusion reaction, they participate in Ca2+ and Delta mu(H)(+) homeostasis. Fusion itself does not require the maintenance of trans-SNARE pairs.

引用

页码：11194 / 11199

页数：6

共 42 条

[21] DISTINCT BIOCHEMICAL REQUIREMENTS FOR THE BUDDING, TARGETING, AND FUSION OF ER-DERIVED TRANSPORT VESICLES [J].

REXACH, MF ;

SCHEKMAN, RW .

JOURNAL OF CELL BIOLOGY, 1991, 114 (02) :219-229

[22] Protein sorting by transport vesicles [J].

Rothman, JE ;

Wieland, FT .

SCIENCE, 1996, 272 (5259) :227-234

[23] MECHANISM OF INTRACELLULAR PROTEIN-TRANSPORT [J].

ROTHMAN, JE .

NATURE, 1994, 372 (6501) :55-63

[24] Functional reconstitution of Ypt7p GTPase and a purified vacuole SNARE complex [J].

Sato, K ;

Wickner, W .

SCIENCE, 1998, 281 (5377) :700-702

[25] Vam7p, a SNAP-25-like molecule, and Vam3p, a syntaxin homolog, function together in yeast vacuolar protein trafficking [J].

Sato, TK ;

Darsow, T ;

Emr, SD .

MOLECULAR AND CELLULAR BIOLOGY, 1998, 18 (09) :5308-5319

[26]

Schekman R, 1998, NATURE, V396, P514, DOI 10.1038/24986

[27]

SEIDLER NW, 1989, J BIOL CHEM, V264, P17816

[28] THE SYNAPTIC VESICLE CYCLE - A CASCADE OF PROTEIN-PROTEIN INTERACTIONS [J].

SUDHOF, TC .

NATURE, 1995, 375 (6533) :645-653

[29] Three v-SNAREs and two t-SNAREs, present in a pentameric cis-SNARE complex on isolated vacuoles, are essential for homotypic fusion [J].

Ungermann, C ;

von Mollard, GF ;

Jensen, ON ;

Margolis, N ;

Stevens, TH ;

Wickner, W .

JOURNAL OF CELL BIOLOGY, 1999, 145 (07) :1435-1442

[30] Vam7p, a vacuolar SNAP-25 homolog, is required for SNARE complex integrity and vacuole docking and fusion [J].

Ungermann, C ;

Wickner, W .

EMBO JOURNAL, 1998, 17 (12) :3269-3276

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