Wess T J, Purslow P P, Kielty C M
Department of Biological and Molecular Sciences, University of Stirling, UK.
FEBS Lett. 1997 Aug 25;413(3):424-8. doi: 10.1016/s0014-5793(97)00950-2.
Microfibrils are ubiquitous matrix polymers which are thought to provide elastic properties in all extracellular matrix structures. The major component of the elastic microfibrils is the protein fibrillin; its molecular structure is unknown. In electron microscopy, microfibrils appear as beaded structures exhibiting a variable periodicity, indicating that they may be elastomeric. The X-ray diffraction of fibrillin-rich microfibrils in the form of zonular filaments from bovine eyes exhibits meridional diffraction peaks indexing on a fundamental periodicity of 55 nm in the relaxed state. The application of a 40% extension produced a lengthening of the periodicity by 3% as judged by alteration of the D spacing of the principal peaks. This effect was shown to be reversible. Changes in the periodicity of the meridional reflections indicate changes in the fundamental structure of the microfilaments, but cannot account for all long range elastomeric properties of fibrillin-containing microfibrils.
微原纤维是普遍存在的基质聚合物，被认为在所有细胞外基质结构中提供弹性特性。弹性微原纤维的主要成分是原纤蛋白；其分子结构尚不清楚。在电子显微镜下，微原纤维呈现为具有可变周期性的串珠状结构，表明它们可能具有弹性。来自牛眼的带状细丝形式的富含原纤蛋白的微原纤维的X射线衍射在松弛状态下呈现出以55nm基本周期性为指标的子午线衍射峰。通过主要峰的D间距的改变判断，施加40%的拉伸会使周期性延长3%。这种效应被证明是可逆的。子午线反射周期性的变化表明微丝基本结构的变化，但不能解释含原纤蛋白的微原纤维的所有长程弹性特性。
