1O1B

MOLECULAR MODELS OF AVERAGED RIGOR CROSSBRIDGES FROM TOMOGRAMS OF INSECT FLIGHT MUSCLE

1O1B の概要

• エントリーDOI: 10.2210/pdb1o1b/pdb
• 関連するPDBエントリー: 1M8Q 1MVW 1O18 1O19 1O1A
• EMDBエントリー: 1001
• 分子名称: SKELETAL MUSCLE MYOSIN II, SKELETAL MUSCLE MYOSIN II REGULATORY LIGHT CHAIN, SKELETAL MUSCLE MYOSIN II ESSENTIAL LIGHT CHAIN, ... (4 entities in total)
• 機能のキーワード: actin-myosin complex in situ in muscle, contractile protein
• 由来する生物種: Gallus gallus (chicken); 詳細
• タンパク質・核酸の鎖数: 26
• 化学式量合計: 1101086.37

構造登録者

Chen, L.F.,Winkler, H.,Reedy, M.K.,Reedy, M.C.,Taylor, K.A. (登録日: 2002-11-15, 公開日: 2002-12-04, 最終更新日: 2023-12-27)

主引用文献

Chen, L.F.,Winkler, H.,Reedy, M.K.,Reedy, M.C.,Taylor, K.A.
Molecular Modeling of Averaged Rigor Crossbridges from Tomograms of Insect Flight Muscle
J.Struct.Biol., 138:92-104, 2002

PubMed Abstract: Electron tomography, correspondence analysis, molecular model building, and real-space refinement provide detailed 3-D structures for in situ myosin crossbridges in the nucleotide-free state (rigor), thought to represent the end of the power stroke. Unaveraged tomograms from a 25-nm longitudinal section of insect flight muscle preserved native structural variation. Recurring crossbridge motifs that repeat every 38.7 nm along the actin filament were extracted from the tomogram and classified by correspondence analysis into 25 class averages, which improved the signal to noise ratio. Models based on the atomic structures of actin and of myosin subfragment 1 were rebuilt to fit 11 class averages. A real-space refinement procedure was applied to quantitatively fit the reconstructions and to minimize steric clashes between domains introduced during the fitting. These combined procedures show that no single myosin head structure can fit all the in situ crossbridges. The validity of the approach is supported by agreement of these atomic models with fluorescent probe data from vertebrate muscle as well as with data from regulatory light chain crosslinking between heads of smooth muscle heavy meromyosin when bound to actin.

PubMed: 12160705
DOI: 10.1016/S1047-8477(02)00013-8

実験手法

ELECTRON MICROSCOPY (70 Å)