A soluble SNARE drives rapid docking, bypassing ATP and Sec17/18p for vacuole fusion

Naomi Thorngren, Kevin Collins, Rutilio A. Fratti, William Wickner, Alexey J. Merz

Research output: Contribution to journalArticle

77 Citations (Scopus)

Abstract

Membrane fusion requires priming, the disassembly of cis-SNARE complexes by the ATP-driven chaperones Sec18/17p. Yeast vacuole priming releases Vam7p, a soluble SNARE. Vam7p reassociation during docking allows trans-SNARE pairing and fusion. We now report that recombinant Vam7p (rVam7p) enters into complex with other SNAREs in vitro and bypasses the need for Sec17p, Sec18p, and ATP. Thus, the sole essential function of vacuole priming in vitro is the release of Vam7p from cis-SNARE complexes. In 'bypass fusion', without ATP but with added rVam7p, there are sufficient unpaired vacuolar SNAREs Vam3p, Vti1p, and Nyv1p to interact with Vam7p and support fusion. However, active SNARE proteins are not sufficient for bypass fusion. rVam7p does not bypass requirements for Rho GTPases, Vps33p, Vps39p, Vps41p, calmodulin, specific lipids, or Vph1p, a subunit of the VATPase. With excess rVam7p, reduced levels of PI(3)P or functional Ypt7p suffice for bypass fusion. High concentrations of rVam7p allow the R-SNARE Ykt6p to substitute for Nyv1p for fusion; this functional redundancy among vacuole SNAREs may explain why nyv1Δ strains lack the vacuole fragmentation seen with mutants in other fusion catalysts.

Original languageEnglish (US)
Pages (from-to)2765-2776
Number of pages12
JournalEMBO Journal
Volume23
Issue number14
DOIs
StatePublished - Jul 21 2004
Externally publishedYes

Fingerprint

SNARE Proteins
Vacuoles
Fusion reactions
Adenosine Triphosphate
rho GTP-Binding Proteins
Membrane Fusion
Calmodulin
Yeast
Redundancy
Yeasts
Membranes
Lipids
Catalysts

Keywords

  • Membrane fusion
  • Nyv1p
  • Sec18p
  • Vam7p
  • Yeast vacuoles

ASJC Scopus subject areas

  • Genetics
  • Cell Biology

Cite this

A soluble SNARE drives rapid docking, bypassing ATP and Sec17/18p for vacuole fusion. / Thorngren, Naomi; Collins, Kevin; Fratti, Rutilio A.; Wickner, William; Merz, Alexey J.

In: EMBO Journal, Vol. 23, No. 14, 21.07.2004, p. 2765-2776.

Research output: Contribution to journalArticle

Thorngren, Naomi ; Collins, Kevin ; Fratti, Rutilio A. ; Wickner, William ; Merz, Alexey J. / A soluble SNARE drives rapid docking, bypassing ATP and Sec17/18p for vacuole fusion. In: EMBO Journal. 2004 ; Vol. 23, No. 14. pp. 2765-2776.
@article{9e4cd81975464a78a2e821a510f54910,
title = "A soluble SNARE drives rapid docking, bypassing ATP and Sec17/18p for vacuole fusion",
abstract = "Membrane fusion requires priming, the disassembly of cis-SNARE complexes by the ATP-driven chaperones Sec18/17p. Yeast vacuole priming releases Vam7p, a soluble SNARE. Vam7p reassociation during docking allows trans-SNARE pairing and fusion. We now report that recombinant Vam7p (rVam7p) enters into complex with other SNAREs in vitro and bypasses the need for Sec17p, Sec18p, and ATP. Thus, the sole essential function of vacuole priming in vitro is the release of Vam7p from cis-SNARE complexes. In 'bypass fusion', without ATP but with added rVam7p, there are sufficient unpaired vacuolar SNAREs Vam3p, Vti1p, and Nyv1p to interact with Vam7p and support fusion. However, active SNARE proteins are not sufficient for bypass fusion. rVam7p does not bypass requirements for Rho GTPases, Vps33p, Vps39p, Vps41p, calmodulin, specific lipids, or Vph1p, a subunit of the VATPase. With excess rVam7p, reduced levels of PI(3)P or functional Ypt7p suffice for bypass fusion. High concentrations of rVam7p allow the R-SNARE Ykt6p to substitute for Nyv1p for fusion; this functional redundancy among vacuole SNAREs may explain why nyv1Δ strains lack the vacuole fragmentation seen with mutants in other fusion catalysts.",
keywords = "Membrane fusion, Nyv1p, Sec18p, Vam7p, Yeast vacuoles",
author = "Naomi Thorngren and Kevin Collins and Fratti, {Rutilio A.} and William Wickner and Merz, {Alexey J.}",
year = "2004",
month = "7",
day = "21",
doi = "10.1038/sj.emboj.7600286",
language = "English (US)",
volume = "23",
pages = "2765--2776",
journal = "EMBO Journal",
issn = "0261-4189",
publisher = "Nature Publishing Group",
number = "14",

}

TY - JOUR

T1 - A soluble SNARE drives rapid docking, bypassing ATP and Sec17/18p for vacuole fusion

AU - Thorngren, Naomi

AU - Collins, Kevin

AU - Fratti, Rutilio A.

AU - Wickner, William

AU - Merz, Alexey J.

PY - 2004/7/21

Y1 - 2004/7/21

N2 - Membrane fusion requires priming, the disassembly of cis-SNARE complexes by the ATP-driven chaperones Sec18/17p. Yeast vacuole priming releases Vam7p, a soluble SNARE. Vam7p reassociation during docking allows trans-SNARE pairing and fusion. We now report that recombinant Vam7p (rVam7p) enters into complex with other SNAREs in vitro and bypasses the need for Sec17p, Sec18p, and ATP. Thus, the sole essential function of vacuole priming in vitro is the release of Vam7p from cis-SNARE complexes. In 'bypass fusion', without ATP but with added rVam7p, there are sufficient unpaired vacuolar SNAREs Vam3p, Vti1p, and Nyv1p to interact with Vam7p and support fusion. However, active SNARE proteins are not sufficient for bypass fusion. rVam7p does not bypass requirements for Rho GTPases, Vps33p, Vps39p, Vps41p, calmodulin, specific lipids, or Vph1p, a subunit of the VATPase. With excess rVam7p, reduced levels of PI(3)P or functional Ypt7p suffice for bypass fusion. High concentrations of rVam7p allow the R-SNARE Ykt6p to substitute for Nyv1p for fusion; this functional redundancy among vacuole SNAREs may explain why nyv1Δ strains lack the vacuole fragmentation seen with mutants in other fusion catalysts.

AB - Membrane fusion requires priming, the disassembly of cis-SNARE complexes by the ATP-driven chaperones Sec18/17p. Yeast vacuole priming releases Vam7p, a soluble SNARE. Vam7p reassociation during docking allows trans-SNARE pairing and fusion. We now report that recombinant Vam7p (rVam7p) enters into complex with other SNAREs in vitro and bypasses the need for Sec17p, Sec18p, and ATP. Thus, the sole essential function of vacuole priming in vitro is the release of Vam7p from cis-SNARE complexes. In 'bypass fusion', without ATP but with added rVam7p, there are sufficient unpaired vacuolar SNAREs Vam3p, Vti1p, and Nyv1p to interact with Vam7p and support fusion. However, active SNARE proteins are not sufficient for bypass fusion. rVam7p does not bypass requirements for Rho GTPases, Vps33p, Vps39p, Vps41p, calmodulin, specific lipids, or Vph1p, a subunit of the VATPase. With excess rVam7p, reduced levels of PI(3)P or functional Ypt7p suffice for bypass fusion. High concentrations of rVam7p allow the R-SNARE Ykt6p to substitute for Nyv1p for fusion; this functional redundancy among vacuole SNAREs may explain why nyv1Δ strains lack the vacuole fragmentation seen with mutants in other fusion catalysts.

KW - Membrane fusion

KW - Nyv1p

KW - Sec18p

KW - Vam7p

KW - Yeast vacuoles

UR - http://www.scopus.com/inward/record.url?scp=3542999933&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=3542999933&partnerID=8YFLogxK

U2 - 10.1038/sj.emboj.7600286

DO - 10.1038/sj.emboj.7600286

M3 - Article

C2 - 15241469

AN - SCOPUS:3542999933

VL - 23

SP - 2765

EP - 2776

JO - EMBO Journal

JF - EMBO Journal

SN - 0261-4189

IS - 14

ER -