Navizet Isabelle, Lavery Richard, Jernigan Robert L
Molecular Structure Section, Laboratory of Experimental and Computational Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-5677, USA.
Proteins. 2004 Feb 15;54(3):384-93. doi: 10.1002/prot.10476.
The movement of the myosin motor along an actin filament involves a directed conformational change within the cross-bridge formed between the protein and the filament. Despite the structural data that has been obtained on this system, little is known of the mechanics of this conformational change. We have used existing crystallographic structures of three conformations of the myosin head, containing the motor domain and the lever arm, for structural comparisons and mechanical studies with a coarse-grained elastic network model. The results enable us to define structurally conserved domains within the protein and to better understand myosin flexibility. Notably they point to the role of the light chains in rigidifying the lever arm and to changes in flexibility as a consequence of nucleotide binding.
肌球蛋白马达沿着肌动蛋白丝的运动涉及到该蛋白质与肌动蛋白丝之间形成的横桥内的定向构象变化。尽管已经获得了关于该系统的结构数据，但对于这种构象变化的机制却知之甚少。我们利用现有的肌球蛋白头部三种构象的晶体结构，这些结构包含马达结构域和杠杆臂，通过粗粒度弹性网络模型进行结构比较和力学研究。这些结果使我们能够在蛋白质中定义结构保守结构域，并更好地理解肌球蛋白的灵活性。值得注意的是，它们指出了轻链在使杠杆臂变硬中的作用以及核苷酸结合导致的灵活性变化。
