EMDB/PDB/SASBDBから引用されている文献のデータベース

キーワード
構造解析手法	All X線回折 NMR 電子顕微鏡小角散乱中性子線回折線維回折粉末回折赤外分光 EPR FRET 理論モデルハイブリッド
著者・登録者
ジャーナル
IF	>30 >20 >10 >5 all

タイトル	Troponin Structural Dynamics in the Native Cardiac Thin Filament Revealed by Cryo Electron Microscopy.
ジャーナル・号・ページ	J Mol Biol, Vol. 436, Issue 6, Page 168498, Year 2024
掲載日	2024年2月20日
著者	Cristina M Risi / Betty Belknap / Jennifer Atherton / Isabella Leite Coscarella / Howard D White / P Bryant Chase / Jose R Pinto / Vitold E Galkin /
PubMed 要旨	Cardiac muscle contraction occurs due to repetitive interactions between myosin thick and actin thin filaments (TF) regulated by Ca levels, active cross-bridges, and cardiac myosin-binding protein C ...Cardiac muscle contraction occurs due to repetitive interactions between myosin thick and actin thin filaments (TF) regulated by Ca levels, active cross-bridges, and cardiac myosin-binding protein C (cMyBP-C). The cardiac TF (cTF) has two nonequivalent strands, each comprised of actin, tropomyosin (Tm), and troponin (Tn). Tn shifts Tm away from myosin-binding sites on actin at elevated Ca levels to allow formation of force-producing actomyosin cross-bridges. The Tn complex is comprised of three distinct polypeptides - Ca-binding TnC, inhibitory TnI, and Tm-binding TnT. The molecular mechanism of their collective action is unresolved due to lack of comprehensive structural information on Tn region of cTF. C1 domain of cMyBP-C activates cTF in the absence of Ca to the same extent as rigor myosin. Here we used cryo-EM of native cTFs to show that cTF Tn core adopts multiple structural conformations at high and low Ca levels and that the two strands are structurally distinct. At high Ca levels, cTF is not entirely activated by Ca but exists in either partially or fully activated state. Complete dissociation of TnI C-terminus is required for full activation. In presence of cMyBP-C C1 domain, Tn core adopts a fully activated conformation, even in absence of Ca. Our data provide a structural description for the requirement of myosin to fully activate cTFs and explain increased affinity of TnC to Ca in presence of active cross-bridges. We suggest that allosteric coupling between Tn subunits and Tm is required to control actomyosin interactions.
リンク	J Mol Biol / PubMed:38387550 / PubMed Central
手法	EM (単粒子)
解像度	5.1 - 7.1 Å
構造データ	42681 8uww EMDB-42681, PDB-8uww: The structure of the native cardiac thin filament troponin core in Ca2+-free state from the upper strand 手法: EM (単粒子) / 解像度: 5.1 Å 42682 8uwx EMDB-42682, PDB-8uwx: The structure of the native cardiac thin filament troponin core in Ca2+-free tilted state from the upper strand 手法: EM (単粒子) / 解像度: 6.0 Å 42683 8uwy EMDB-42683, PDB-8uwy: The structure of the native cardiac thin filament troponin core in Ca2+-free rotated state from the upper strand 手法: EM (単粒子) / 解像度: 5.5 Å 42800 8uyd EMDB-42800, PDB-8uyd: The structure of the native cardiac thin filament troponin core in Ca2+-free state from the lower strand 手法: EM (単粒子) / 解像度: 5.3 Å 42833 8uz5 EMDB-42833, PDB-8uz5: The structure of the native cardiac thin filament troponin core in Ca2+-free rotated state from the lower strand 手法: EM (単粒子) / 解像度: 5.9 Å 42835 8uz6 EMDB-42835, PDB-8uz6: The structure of the native cardiac thin filament troponin core in Ca2+-free tilted state from the lower strand 手法: EM (単粒子) / 解像度: 7.1 Å 42846 8uzx EMDB-42846, PDB-8uzx: The structure of the native cardiac thin filament troponin core in Ca2+-bound fully activated state from the upper strand 手法: EM (単粒子) / 解像度: 5.4 Å 42847 8uzy EMDB-42847, PDB-8uzy: The structure of the native cardiac thin filament troponin core in Ca2+-bound partially activated state from the upper strand 手法: EM (単粒子) / 解像度: 5.3 Å 42849 8v01 EMDB-42849, PDB-8v01: The structure of the native cardiac thin filament troponin core in Ca2+-bound fully activated state 1 from the lower strand 手法: EM (単粒子) / 解像度: 5.5 Å 42856 8v0i EMDB-42856, PDB-8v0i: The structure of the native cardiac thin filament troponin core in Ca2+-bound fully activated state 2 from the lower strand 手法: EM (単粒子) / 解像度: 5.8 Å 42858 8v0k EMDB-42858, PDB-8v0k: The structure of the native cardiac thin filament troponin core in Ca2+-bound partially activated state from the lower strand 手法: EM (単粒子) / 解像度: 5.2 Å 42874 8v0y EMDB-42874, PDB-8v0y: The structure of the native cardiac thin filament troponin core in Ca2+-free state from the upper strand activated by the C1-domain of cardiac myosin binding protein C 手法: EM (単粒子) / 解像度: 7.0 Å
化合物	ChemComp-ADP: ADENOSINE-5'-DIPHOSPHATE / ADP / ADP, エネルギー貯蔵分子YM ChemComp-MG: Unknown entry / マグネシウムジカチオン ChemComp-CA*: Unknown entry / カルシウムジカチオン
由来	sus scrofa (ブタ)
キーワード	MOTOR PROTEIN / thin filament / troponin / tropomyosin / cryo-EM / muscle structure / myosin binding protein C