#2: ジャーナル: Proc Natl Acad Sci U S A / 年: 2006 タイトル: Crystal structures of human cardiac beta-myosin II S2-Delta provide insight into the functional role of the S2 subfragment. 著者: Wulf Blankenfeldt / Nicolas H Thomä / John S Wray / Mathias Gautel / Ilme Schlichting / 要旨: Myosin II is the major component of the muscle thick filament. It consists of two N-terminal S1 subfragments ("heads") connected to a long dimeric coiled-coil rod. The rod is in itself twofold ...Myosin II is the major component of the muscle thick filament. It consists of two N-terminal S1 subfragments ("heads") connected to a long dimeric coiled-coil rod. The rod is in itself twofold symmetric, but in the filament, the two heads point away from the filament surface and are therefore not equivalent. This breaking of symmetry requires the initial section of the rod, subfragment 2 (S2), to be relatively flexible. S2 is an important functional element, involved in various mechanisms by which the activity of smooth and striated muscle is regulated. We have determined crystal structures of the 126 N-terminal residues of S2 from human cardiac beta-myosin II (S2-Delta), of both WT and the disease-associated E924K mutant. S2-Delta is a straight parallel dimeric coiled coil, but the N terminus of one chain is disordered in WT-S2-Delta due to crystal contacts, indicative of unstable local structure. Bulky noncanonical side chains pack into a/d positions of S2-Delta's N terminus, leading to defined local asymmetry and axial stagger, which could induce nonequivalence of the S1 subfragments. Additionally, S2 possesses a conserved charge distribution with three prominent rings of negative potential within S2-Delta, the first of which may provide a binding interface for the "blocked head" of smooth muscle myosin in the OFF state. The observation that many disease-associated mutations affect the second negatively charged ring further suggests that charge interactions play an important role in regulation of cardiac muscle activity through myosin-binding protein C.
SEQUENCE THE PEPTIDE CONTAINS A GSHM TETRAPEPTIDE, FOLLOWED BY THE N-TERMINAL 51 RESIDUES OF THE ... SEQUENCE THE PEPTIDE CONTAINS A GSHM TETRAPEPTIDE, FOLLOWED BY THE N-TERMINAL 51 RESIDUES OF THE BAY SCALLOP MYOSIN ROD (RESIDUES 835-885 OF THE BAY SCALLOP MYOSIN HEAVY CHAIN, GI:5612), FOLLOWED BY A GS LINKER, FOLLOWED BY THE LEUCINE ZIPPER OF THE YEAST GCN4 TRANSCRIPTION FACTOR (RESIDUES 250-281 OF GI:171584 DENOTED AS RESIDUES 888-919 IN THE SUBMITTED COORDINATES).
#241 - 2020年1月 20年の分子を振り返って (Twenty Years of Molecules) 類似性 (1)
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集合体
登録構造単位
A: Myosin heavy chain, striated muscle/General control protein GCN4 chimera B: Myosin heavy chain, striated muscle/General control protein GCN4 chimera ヘテロ分子
温度: 277 K / 手法: 蒸気拡散法, ハンギングドロップ法 / pH: 7.2 詳細: 1.5 microliter of protein solution (4 mg/ml protein in 30 mM MOPS buffer pH 7.2, 40 mM NaCl, 2 mM NaN3) mixed with 3 microliters of (16.6% PEG 3350, 4.6% MPD, 13 mM NaCl, 2 mM NaN3, 10 mM ...詳細: 1.5 microliter of protein solution (4 mg/ml protein in 30 mM MOPS buffer pH 7.2, 40 mM NaCl, 2 mM NaN3) mixed with 3 microliters of (16.6% PEG 3350, 4.6% MPD, 13 mM NaCl, 2 mM NaN3, 10 mM MOPS pH 7.2) and equilibrated against (15% PEG 3350, 4.2% MPD, 18 mM MOPS, 24 mM NaCl), VAPOR DIFFUSION, HANGING DROP, temperature 277K
タイプ: ADSC QUANTUM 210 / 検出器: CCD 詳細: Bent triangular asymmetric cut Si(111) monochromator for horizontal focusing, and Rh-coated Si mirror for vertical focusing.
放射
モノクロメーター: Si(111) / プロトコル: SINGLE WAVELENGTH / 単色(M)・ラウエ(L): M / 散乱光タイプ: x-ray
放射波長
波長: 0.9764 Å / 相対比: 1
反射
解像度: 2.3→50 Å / Num. obs: 8283 / % possible obs: 84.9 % / 冗長度: 3.3 % / Rmerge(I) obs: 0.082 / Χ2: 1.544 / Net I/σ(I): 9.9