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Rapid and efficient fusion of phospholipid vesicles by the alpha-helical core of a SNARE complex in the absence of an N-terminal regulatory domain.

ABSTRACT: A protease-resistant core domain of the neuronal SNARE complex consists of an alpha-helical bundle similar to the proposed fusogenic core of viral fusion proteins [Skehel, J. J. & Wiley, D. C. (1998) Cell 95, 871-874]. We find that the isolated core of a SNARE complex efficiently fuses artificial bilayers and does so faster than full length SNAREs. Unexpectedly, a dramatic increase in speed results from removal of the N-terminal domain of the t-SNARE syntaxin, which does not affect the rate of assembly of v-t SNARES. In the absence of this negative regulatory domain, the half-time for fusion of an entire population of lipid vesicles by isolated SNARE cores ( approximately 10 min) is compatible with the kinetics of fusion in many cell types.

SUBMITTER: Parlati F

PROVIDER: S-EPMC22992 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature

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Rapid and efficient fusion of phospholipid vesicles by the alpha-helical core of a SNARE complex in the absence of an N-terminal regulatory domain.

Parlati F F Weber T T McNew J A JA Westermann B B Söllner T H TH Rothman J E JE

Proceedings of the National Academy of Sciences of the United States of America 19991001 22

A protease-resistant core domain of the neuronal SNARE complex consists of an alpha-helical bundle similar to the proposed fusogenic core of viral fusion proteins [Skehel, J. J. & Wiley, D. C. (1998) Cell 95, 871-874]. We find that the isolated core of a SNARE complex efficiently fuses artificial bilayers and does so faster than full length SNAREs. Unexpectedly, a dramatic increase in speed results from removal of the N-terminal domain of the t-SNARE syntaxin, which does not affect the rate of a ...[more]

PMID: 10535962

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