Internal strain drives spontaneous periodic buckling in collagen and regulates remodeling
Internal strain drives spontaneous periodic buckling in collagen and regulates remodeling
复制标题
DOI：
10.1073/pnas.1523228113
复制
发表时间：
2016-07-26
影响因子：
11.1
通讯作者：
Neuman, Keir C.
中科院分区：
文献类型：
--
作者：
Dittmore, Andrew;Silver, Jonathan;Neuman, Keir C.
Fibrillar collagen, an essential structural component of the extracellular matrix, is remarkably resistant to proteolysis, requiring specialized matrix metalloproteinases (MMPs) to initiate its remodeling. In the context of native fibrils, remodeling is poorly understood; MMPs have limited access to cleavage sites and are inhibited by tension on the fibril. Here, single-molecule recordings of fluorescently labeled MMPs reveal cleavage-vulnerable binding regions arrayed periodically at similar to 1-mu m intervals along collagen fibrils. Binding regions remain periodic even as they migrate on the fibril, indicating a collective process of thermally activated and self-healing defect formation. An internal strain relief model involving reversible structural rearrangements quantitatively reproduces the observed spatial patterning and fluctuations of defects and provides a mechanism for tension-dependent stabilization of fibrillar collagen. This work identifies internal-strain-driven defects that may have general and widespread regulatory functions in self-assembled biological filaments.
