Flexibility of smooth and skeletal tropomyosins.
Flexibility of smooth and skeletal tropomyosins.
复制标题
光滑和骨骼原肌球蛋白的灵活性。
DOI：
10.1002/bip.360280504
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发表时间：
1989
期刊：
影响因子：
2.9
通讯作者：
Stellwagen,NC
中科院分区：
文献类型：
--
作者：
Swenson,CA;Stellwagen,NC
通过分析不同温度和盐浓度下零场双折射的衰减来测量不可聚合的骨骼和平滑肌原肌球蛋白的旋转弛豫时间。溶液中的骨骼原肌球蛋白同样可以很好地建模为刚性棒或持续长度为 150 nm 的半柔性棒。平滑肌原肌球蛋白不适合刚性杆模型，但可以通过持续长度为 55 nm 的半柔性杆模型很好地近似。结果表明，平滑肌原肌球蛋白要么是比骨骼肌原肌球蛋白更灵活的分子，要么是端到端长度短于卷曲螺旋轮廓长度的弯曲结构。平滑肌原肌球蛋白对肌动球蛋白 ATP 酶的控制方式与骨骼肌原肌球蛋白不同，有人认为原因是它更坚硬。显然，必须寻求另一种解释。
The rotational relaxation times of nonpolymerizable skeletal and smooth muscle tropomyosin were measured by analysis of the decay of the zero‐field birefringence at different temperatures and salt concentrations. Skeletal tropomyosin in solution is equally well modeled as a rigid rod or as a semiflexible rod with a persistence length of 150 nm. Smooth muscle tropomyosin does not fit the rigid rod model but is well approximated by a semiflexible rod model with a persistence length of 55 nm. The results indicate that smooth muscle tropomyosin is either a more flexible molecule than skeletal muscle tropomyosin or is a curved structure with an end‐to‐end length shorter than the coiled‐coil contour length. Smooth muscle tropomyosin controls the actomyosin ATPase differently from skeletal muscle tropomyosin and it had been suggested that the reason is because it is more rigid; clearly, another explanation must be sought.