Control of heterotypic fibril formation by collages V is determined by chain stoichiometry
Control of heterotypic fibril formation by collages V is determined by chain stoichiometry
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DOI：
10.1074/jbc.m101182200
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发表时间：
2001-06-29
影响因子：
4.8
通讯作者：
Ruggiero, F
中科院分区：
文献类型：
--
作者：
Chanut-Delalande, H;Fichard, A;Ruggiero, F
虽然已知V型胶原异源三聚体参与纤维组装的控制，但同源三聚体在纤维组织中的作用尚未被研究。在这里，大量重组V型胶原同源三聚体的生产使我们能够详细研究它在同型和异型纤维形成中的作用。在胃酶消化去除末端区域后，V型胶原异源三聚体和同源三聚体都形成了细小的同型纤维，这表明直径限制至少部分是V型胶原三螺旋的固有特性。然而，当与I型胶原混合时，不同的互补方法表明，V型胶原异源三聚体和同源三聚体在异型纤维形成中发挥不同的作用。与埋藏在纤维内部的异源三聚体不同，同源三聚体定位于宽广的I型胶原纤维表面的细丝状结构，并不调节纤维组装。它在纤维表面的定位表明，同源三聚体可以作为胶原纤维或细胞外基质中的大分子之间的分子连接物，或两者兼而有之。因此，根据它们在组织中的不同分布，不同的V型胶原亚型可能具有特定的生物学功能。
Although the collagen V heterotrimer is known to be involved in the control of fibril assembly, the role of the homotrimer in fibrillar organization has not yet been examined. Here, the production of substantial amounts of recombinant collagen V homotrimer has allowed a detailed study of its role in homotypic and heterotypic fibril formation. After removal of terminal regions by pepsin digestion, both the collagen V heterotrimer and homotrimer formed thin homotypic fibrils, thus showing that diameter limitation is at least in part an intrinsic property of the collagen V triple helix. When mixed with collagen I, however, various complementary approaches indicated that the collagen V heterotrimer and homotrimer exerted different effects in heterotypic fibril formation. Unlike the heterotrimer, which was buried in the fibril interior, the homotrimer was localized as thin filamentous structures at the surface of wide collagen I fibrils and did not regulate fibril assembly. Its localization at the fibril surface suggests that the homotrimer can act as a molecular linker between collagen fibrils or macromolecules in the extracellular matrix or both. Thus, depending on their respective distribution in tissues, the different collagen V isoforms might fulfill specific biological functions.