1MDU

Crystal structure of the chicken actin trimer complexed with human gelsolin segment 1 (GS-1)

1MDU の概要

• エントリーDOI: 10.2210/pdb1mdu/pdb
• 分子名称: gelsolin precursor, a-actin, CALCIUM ION, ... (6 entities in total)
• 機能のキーワード: gelsolin precursor, a-actin, adenosine-5'-triphosphate, 2-amino-2-hydroxymethyl-propane-1, 3-diol, structural protein
• 由来する生物種: Homo sapiens (human); 詳細
• 細胞内の位置: Cytoplasm, cytoskeleton: P06396; Isoform 2: Cytoplasm, cytoskeleton. Isoform 1: Secreted: P68139
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 113780.66

構造登録者

Dawson, J.F.,Sablin, E.P.,Spudich, J.A.,Fletterick, R.J. (登録日: 2002-08-07, 公開日: 2003-01-07, 最終更新日: 2025-03-26)

主引用文献

Dawson, J.F.,Sablin, E.P.,Spudich, J.A.,Fletterick, R.J.
Structure of an F-actin trimer disrupted by gelsolin and implications for the mechanism of severing
J.Biol.Chem., 278:1229-1238, 2003

PubMed Abstract: Stable oligomers of filamentous actin were obtained by cross-linking F-actin with 1,4-N,N'-phenylenedimaleimide and depolymerization with excess segment-1 of gelsolin. Segment-1-bound and cross-linked actin oligomers containing either two or three actin subunits were purified and shown to nucleate actin assembly. Kinetic assembly data from mixtures of monomeric actin and the actin oligomers fit a nucleation model where cross-linked actin dimer or trimer reacts with an actin monomer to produce a competent nucleus for filament assembly. We report the three-dimensional structure of the segment-1-actin hexamer containing three actin subunits, each with a tightly bound ATP. Comparative analysis of this structure with twelve other actin structures provides an atomic level explanation for the preferential binding of ATP by the segment-1-complexed actin. Although the structure of segment-1-bound actin trimer is topologically similar to the helical model of F-actin (1), it has a distorted symmetry compared with that of the helical model. This distortion results from intercalation of segment-1 between actin protomers that increase the rise per subunit and rotate each of the actin subunits relative to their positions in F-actin. We also show that segment-1 of gelsolin is able to sever actin filaments, although the severing activity of segment-1 is significantly lower than full-length gelsolin.

PubMed: 12356759
DOI: 10.1074/jbc.M209160200

実験手法

X-RAY DIFFRACTION (2.2 Å)