Structural highlights
Function
[VAM3_YEAST] Required for vacuolar assembly. Provides the t-SNARE function in a late step of the vacuolar assembly. Required for homotypic vacuole membrane fusion, autophagy and fusion of biosynthetic transport vesicles with the vacuole. Required for the delivery of alpha-factor receptor-ligand complexes to the vacuole.
Publication Abstract from PubMed
Syntaxins and Sec1/munc18 proteins are central to intracellular membrane fusion. All syntaxins comprise a variable N-terminal region, a conserved SNARE motif that is critical for SNARE complex formation, and a transmembrane region. The N-terminal region of neuronal syntaxin 1A contains a three-helix domain that folds back onto the SNARE motif forming a 'closed' conformation; this conformation is required for munc18-1 binding. We have examined the generality of the structural properties of syntaxins by NMR analysis of Vam3p, a yeast syntaxin essential for vacuolar fusion. Surprisingly, Vam3p also has an N-terminal three-helical domain despite lacking apparent sequence homology with syntaxin 1A in this region. However, Vam3p does not form a closed conformation and its N-terminal domain is not required for binding to the Sec1/munc18 protein Vps33p, suggesting that critical distinctions exist in the mechanisms used by syntaxins to govern different types of membrane fusion.
Vam3p structure reveals conserved and divergent properties of syntaxins.,Dulubova I, Yamaguchi T, Wang Y, Sudhof TC, Rizo J Nat Struct Biol. 2001 Mar;8(3):258-64. PMID:11224573[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Dulubova I, Yamaguchi T, Wang Y, Sudhof TC, Rizo J. Vam3p structure reveals conserved and divergent properties of syntaxins. Nat Struct Biol. 2001 Mar;8(3):258-64. PMID:11224573 doi:10.1038/85012
