4PL7

Structure of Komagataella pastoris actin-thymosin beta4 hybrid

4PL7 の概要

• エントリーDOI: 10.2210/pdb4pl7/pdb
• 関連するPDBエントリー: 4PL8
• 分子名称: Actin,Thymosin beta-4, ADENOSINE-5'-TRIPHOSPHATE, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: structural protein, contractile protein
• 由来する生物種: Komagataella pastoris (Yeast); 詳細
• 細胞内の位置: Cytoplasm, cytoskeleton: P62328
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 98059.96

構造登録者

Xue, B.,Robinson, R.C. (登録日: 2014-05-16, 公開日: 2014-10-22, 最終更新日: 2023-11-08)

主引用文献

Xue, B.,Leyrat, C.,Grimes, J.M.,Robinson, R.C.
Structural basis of thymosin-beta 4/profilin exchange leading to actin filament polymerization.
Proc.Natl.Acad.Sci.USA, 111:E4596-E4605, 2014

PubMed Abstract: Thymosin-β4 (Tβ4) and profilin are the two major sequestering proteins that maintain the pool of monomeric actin (G-actin) within cells of higher eukaryotes. Tβ4 prevents G-actin from joining a filament, whereas profilin:actin only supports barbed-end elongation. Here, we report two Tβ4:actin structures. The first structure shows that Tβ4 has two helices that bind at the barbed and pointed faces of G-actin, preventing the incorporation of the bound G-actin into a filament. The second structure displays a more open nucleotide binding cleft on G-actin, which is typical of profilin:actin structures, with a concomitant disruption of the Tβ4 C-terminal helix interaction. These structures, combined with biochemical assays and molecular dynamics simulations, show that the exchange of bound actin between Tβ4 and profilin involves both steric and allosteric components. The sensitivity of profilin to the conformational state of actin indicates a similar allosteric mechanism for the dissociation of profilin during filament elongation.

PubMed: 25313062
DOI: 10.1073/pnas.1412271111

実験手法

X-RAY DIFFRACTION (2.3 Å)