Department of Physiology and Biophysics, University of Washington, , Seattle, WA, USA.
Proc Biol Sci. 2013 Sep 7;280(1766):20130697. doi: 10.1098/rspb.2013.0697.
Classic interpretations of the striated muscle length-tension curve focus on how force varies with overlap of thin (actin) and thick (myosin) filaments. New models of sarcomere geometry and experiments with skinned synchronous insect flight muscle suggest that changes in the radial distance between the actin and myosin filaments, the filament lattice spacing, are responsible for between 20% and 50% of the change in force seen between sarcomere lengths of 1.4 and 3.4 µm. Thus, lattice spacing is a significant force regulator, increasing the slope of muscle's force-length dependence.
经典的横纹肌长度-张力曲线解释侧重于力如何随细(肌动蛋白)和粗(肌球蛋白)丝的重叠而变化。新的肌节几何模型和对去皮同步昆虫飞行肌的实验表明,肌动蛋白和肌球蛋白丝之间的径向距离(即肌节晶格间距)的变化导致了肌节长度在 1.4 和 3.4 µm 之间的力变化的 20%至 50%。因此,晶格间距是一个重要的力调节因子,增加了肌肉力-长度依赖性的斜率。