Mecham R P, Broekelmann T, Davis E C, Gibson M A, Brown-Augsburger P
Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
Ciba Found Symp. 1995;192:172-81; discussion 181-4. doi: 10.1002/9780470514771.ch9.
To investigate the mechanisms behind elastic fibre assembly, we studied the molecular interactions between elastin and microfibrillar components using solid-phase binding assays. Fibrillin 1, purified from tissue using reductive-saline extraction, showed no binding to microfibril-associated glycoprotein (MAGP) or tropoelastin. MAGP, however, was found to bind specifically to tropoelastin in a divalent-cation independent manner. Antibody inhibition studies indicated that the C-terminus of tropoelastin defined the interactive site with MAGP. MAGP and fibrillin were also substrates for transglutaminase, which may provide an important mechanism for stabilizing microfibrillar structure. In other studies we found that a major cross-linking region in elastin is formed through the association of domains encoded by exons 10, 19 and 25 of tropoelastin and that the three chains are joined together by one desmosine and two lysinonorleucine cross-links.
为了研究弹性纤维组装背后的机制，我们使用固相结合试验研究了弹性蛋白与微原纤维成分之间的分子相互作用。使用还原盐溶液从组织中纯化的原纤蛋白1未显示与微原纤维相关糖蛋白（MAGP）或原弹性蛋白结合。然而，发现MAGP以不依赖二价阳离子的方式特异性结合原弹性蛋白。抗体抑制研究表明，原弹性蛋白的C末端定义了与MAGP的相互作用位点。MAGP和原纤蛋白也是转谷氨酰胺酶的底物，这可能为稳定微原纤维结构提供重要机制。在其他研究中，我们发现弹性蛋白中的一个主要交联区域是通过原弹性蛋白外显子10、19和25编码的结构域的结合形成的，并且三条链通过一个锁链素和两个赖氨酰正亮氨酸交联连接在一起。
