7QIN

In situ structure of actomyosin complex in skeletal sarcomere

7QIN の概要

• エントリーDOI: 10.2210/pdb7qin/pdb
• 関連するPDBエントリー: 7QIM 7QIO
• EMDBエントリー: 13990 13991 13992 13993 13998
• 分子名称: Actin, alpha skeletal muscle, nebulin (mouse), tropomyosin, alpha-1 (mouse), ... (9 entities in total)
• 機能のキーワード: skeletal muscle, sarcomere, thin filament, cross-bridge, contractile protein
• 由来する生物種: Mus musculus (house mouse); 詳細
• タンパク質・核酸の鎖数: 13
• 化学式量合計: 452374.78

構造登録者

Wang, Z.,Grange, M.,Pospich, S.,Wagner, T.,Kho, A.L.,Gautel, M.,Raunser, S. (登録日: 2021-12-15, 公開日: 2022-02-16, 最終更新日: 2026-03-04)

主引用文献

Wang, Z.,Grange, M.,Pospich, S.,Wagner, T.,Kho, A.L.,Gautel, M.,Raunser, S.
Structures from intact myofibrils reveal mechanism of thin filament regulation through nebulin.
Science, 375:eabn1934-eabn1934, 2022

PubMed Abstract: In skeletal muscle, nebulin stabilizes and regulates the length of thin filaments, but the underlying mechanism remains nebulous. In this work, we used cryo-electron tomography and subtomogram averaging to reveal structures of native nebulin bound to thin filaments within intact sarcomeres. This in situ reconstruction provided high-resolution details of the interaction between nebulin and actin, demonstrating the stabilizing role of nebulin. Myosin bound to the thin filaments exhibited different conformations of the neck domain, highlighting its inherent structural variability in muscle. Unexpectedly, nebulin did not interact with myosin or tropomyosin, but it did interact with a troponin T linker through two potential binding motifs on nebulin, explaining its regulatory role. Our structures support the role of nebulin as a thin filament "molecular ruler" and provide a molecular basis for studying nemaline myopathies.

PubMed: 35175800
DOI: 10.1126/science.abn1934

実験手法

ELECTRON MICROSCOPY (6.6 Å)