The Habc domain and the SNARE core complex are connected by a highly flexible linker.

Details

Serval ID
serval:BIB_E6958DE88E41
Type
Article: article from journal or magazin.
Collection
Publications
Title
The Habc domain and the SNARE core complex are connected by a highly flexible linker.
Journal
Biochemistry
Author(s)
Margittai M., Fasshauer D., Jahn R., Langen R.
ISSN
0006-2960 (Print)
ISSN-L
0006-2960
Publication state
Published
Issued date
2003
Peer-reviewed
Oui
Volume
42
Number
14
Pages
4009-4014
Language
english
Abstract
Syntaxin 1a is a member of the SNARE superfamily of small, mostly membrane-bound proteins that mediate membrane fusion in all eukaryotic cells. Upon membrane fusion, syntaxin 1 forms a stable complex with its partner SNAREs. Syntaxin contains a C-terminal transmembrane domain, an adjacent SNARE motif that interacts with its partner SNAREs, and an N-terminal Habc domain. The Habc domain reversibly folds back upon the SNARE motif, resulting in a "closed" conformation that is stabilized by binding to the protein munc18. The SNARE motif and the Habc domain are separated by a linker region of about 40 amino acids. When syntaxin is complexed with munc18, the linker is structured and consists of a mix of turns and small alpha-helices. When syntaxin is complexed with its partner SNAREs, the Habc domain is dissociated, but the structure of the linker region is not known. Here we used site-directed spin labeling and EPR spectroscopy to determine the structure of the linker region of syntaxin in the SNARE complex. We found that the entire linker region of syntaxin is unstructured except for three residues at the N-terminal and six residues at the C-terminal boundary whereas the structures of the flanking regions in the Habc domain and the SNARE motif correspond to the high-resolution structures of the isolated fragments. We conclude that the linker region exhibits a high degree of conformational flexibility.
Keywords
Amino Acid Motifs, Electron Spin Resonance Spectroscopy, Membrane Proteins/chemistry, Qa-SNARE Proteins, SNARE Proteins, Spin Labels, Vesicular Transport Proteins
Pubmed
Web of science
Create date
15/09/2011 9:19
Last modification date
20/08/2019 16:09
Usage data