4PKG

Complex of ATP-actin With the N-terminal Actin-Binding Domain of Tropomodulin

4PKG の概要

• エントリーDOI: 10.2210/pdb4pkg/pdb
• 関連するPDBエントリー: 4PKH 4PKI
• 分子名称: Actin, alpha skeletal muscle, Gelsolin,Tropomodulin-1 chimera, ADENOSINE-5'-TRIPHOSPHATE, ... (5 entities in total)
• 機能のキーワード: tmod, actin filament, pointed-end capping protein, tropomyosin, contractile protein, actin-binding protein, contractile protein-actin-binding protein complex, contractile protein/actin-binding protein
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 63561.79

構造登録者

Rao, J.N.,Dominguez, R. (登録日: 2014-05-14, 公開日: 2014-07-30, 最終更新日: 2023-09-27)

主引用文献

Rao, J.N.,Madasu, Y.,Dominguez, R.
Actin cytoskeleton. Mechanism of actin filament pointed-end capping by tropomodulin.
Science, 345:463-467, 2014

PubMed Abstract: Proteins that cap the ends of the actin filament are essential regulators of cytoskeleton dynamics. Whereas several proteins cap the rapidly growing barbed end, tropomodulin (Tmod) is the only protein known to cap the slowly growing pointed end. The lack of structural information severely limits our understanding of Tmod's capping mechanism. We describe crystal structures of actin complexes with the unstructured amino-terminal and the leucine-rich repeat carboxy-terminal domains of Tmod. The structures and biochemical analysis of structure-inspired mutants showed that one Tmod molecule interacts with three actin subunits at the pointed end, while also contacting two tropomyosin molecules on each side of the filament. We found that Tmod achieves high-affinity binding through several discrete low-affinity interactions, which suggests a mechanism for controlled subunit exchange at the pointed end.

PubMed: 25061212
DOI: 10.1126/science.1256159

実験手法

X-RAY DIFFRACTION (1.8 Å)