Structure and dynamics of γ-SNAP: Insight into flexibility of proteins from the SNAP family

• Published in: Proteins, structure, function, and bioinformatics structure, function, and bioinformatics, 2008-01, Vol.70 (1), p.93-104
• Main Authors: Bitto, Eduard, Bingman, Craig A., Kondrashov, Dmitry A., McCoy, Jason G., Bannen, Ryan M., Wesenberg, Gary E., Phillips Jr, George N.
• Format: Article
• Language: English
• Subjects: Animals; Cattle; Electrochemistry; Electrodes; membrane trafficking; Microscopy, Atomic Force; normal mode analysis; Protein Conformation; SNARE recycling; Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins - chemistry; X-ray structure
• ISSN: 0887-3585; 1097-0134
• DOI: 10.1002/prot.21468

Soluble N‐ethylmaleimide‐sensitive factor attachment protein gamma (γ‐SNAP) is a member of an eukaryotic protein family involved in intracellular membrane trafficking. The X‐ray structure of Brachydanio rerio γ‐SNAP was determined to 2.6 Å and revealed an all‐helical protein comprised of an extended twisted‐sheet of helical hairpins with a helical‐bundle domain on its carboxy‐terminal end. Structural and conformational differences between multiple observed γ‐SNAP molecules and Sec17, a SNAP family protein from yeast, are analyzed. Conformational variation in γ‐SNAP molecules is matched with great precision by the two lowest frequency normal modes of the structure. Comparison of the lowest‐frequency modes from γ‐SNAP and Sec17 indicated that the structures share preferred directions of flexibility, corresponding to bending and twisting of the twisted sheet motif. We discuss possible consequences related to the flexibility of the SNAP proteins for the mechanism of the 20S complex disassembly during the SNAP receptors recycling. Proteins 2008. © 2007 Wiley‐Liss, Inc.