Bonet A, Audemard E, Mornet D
Centre de Recherche de Biochimie Macromoléculaire du CNRS, INSERM U-249 Université de Montpellier I, France.
Biochem Biophys Res Commun. 1988 Apr 15;152(1):1-8. doi: 10.1016/s0006-291x(88)80671-5.
The reaction of the crosslinker dibromobimane has recently revealed a functionally important internal loop structure within the skeletal myosin S1 heavy chain where Cys-522 of the 50K domain and Cys-707 (SH1) of the 20K region are spatially juxtaposed. Here we have studied the possible relevance of this topological feature to the architecture and transducing activity of the myosin head in general, by extending the dibromobimane modification to smooth muscle myosin. Treatment of chicken gizzard myosin S1 with dibromobimane resulted in intramolecular crosslinking between the C-terminal 25K and central 50K segments of the S1 heavy chain. The data suggest a conservation at the 50K-25K interface of smooth muscle S1 heavy chain and the importance of the neighboring SH1 region, whose conformation may play an important role in energy transduction by the myosin head.
交联剂二溴双马来酰亚胺的反应最近揭示了骨骼肌肌球蛋白S1重链内一个功能上重要的内部环结构，其中50K结构域的半胱氨酸-522和20K区域的半胱氨酸-707（SH1）在空间上并列。在这里，我们通过将二溴双马来酰亚胺修饰扩展到平滑肌肌球蛋白，研究了这种拓扑特征与一般肌球蛋白头部结构和转导活性的可能相关性。用二溴双马来酰亚胺处理鸡砂囊肌球蛋白S1导致S1重链C末端25K和中央50K片段之间的分子内交联。数据表明平滑肌S1重链的50K-25K界面存在保守性，以及相邻SH1区域的重要性，其构象可能在肌球蛋白头部的能量转导中起重要作用。
