4NPJ

Extended-Synaptotagmin 2, C2A- and C2B-domains

4NPJ の概要

• エントリーDOI: 10.2210/pdb4npj/pdb
• 関連するPDBエントリー: 4NPK
• 分子名称: Extended synaptotagmin-2, CHLORIDE ION, SODIUM ION, ... (5 entities in total)
• 機能のキーワード: calcium/phospholipid binding protein, c2 domain, membrane traffic, protein targeting, plasma membrane, membrane protein, er to plasma membrane
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Cell membrane; Peripheral membrane protein: A0FGR8
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 68721.58

構造登録者

Tomchick, D.R.,Rizo, J.,Xu, J. (登録日: 2013-11-21, 公開日: 2014-01-29, 最終更新日: 2024-02-28)

主引用文献

Xu, J.,Bacaj, T.,Zhou, A.,Tomchick, D.R.,Sudhof, T.C.,Rizo, J.
Structure and ca(2+)-binding properties of the tandem c2 domains of e-syt2.
Structure, 22:269-280, 2014

PubMed Abstract: Contacts between the endoplasmic reticulum and the plasma membrane involve extended synaptotagmins (E-Syts) in mammals or tricalbins in yeast, proteins with multiple C₂ domains. One of the tandem C₂ domains of E-Syt2 is predicted to bind Ca²⁺, but no Ca²⁺-dependent function has been attributed to this protein. We have determined the crystal structures of the tandem C₂ domains of E-Syt2 in the absence and presence of Ca²⁺ and analyzed their Ca²⁺-binding properties by nuclear magnetic resonance spectroscopy. Our data reveal an unexpected V-shaped structure with a rigid orientation between the two C₂ domains that is not substantially altered by Ca²⁺. The E-Syt2 C2A domain binds up to four Ca²⁺ ions, whereas the C₂B domain does not bind Ca²⁺. These results suggest that E-Syt2 performs an as yet unidentified Ca²⁺-dependent function through its C₂A domain and uncover fundamental differences between the properties of the tandem C₂ domains of E-Syts and synaptotagmins.

PubMed: 24373768
DOI: 10.1016/j.str.2013.11.011

実験手法

X-RAY DIFFRACTION (2.101 Å)