Elastic fibres bind associated proteins

Other proteins found associated with elastic fibres include vitronectin (Dahlback et al. 1989,1990, Hintner et al. 1991) and and a structurally unrelated group of proteins collectively termed microfibrillar-associated proteins (MFAPs) (Gibson et al. 1996, 2000, Abrams et al. 1995, Toyashima et al. 1999). The significance of these interactions is not well understood.

Vitronectin is present in plasma, extracellular matrix, and the alpha granules of blood platelets. It has been implicated as a regulator of many processes including coagulation, fibrinolysis, pericellular proteolysis, complement dependent immune response, cell attachment and spreading (Zhuang et al. 1996). It interacts with integrins alphaVbeta1 (Marshall et al. 1995), alphaVbeta3 (Pytela et al. 1985), alphaVbeta5 (Panetti & McKeown Longo 1993) and alphaIIbBeta3 (Pytela et al. 1986) through Arg Gly Asp (RGD) cell binding sequences.

The MFAPs are not a structurally related family but grouped due to their localization with microfibrils. MFAP1 was originally called 'associated microfibril protein' (AMP). It is a 54 kDa protein, processed to 32 kDa, localizing to fibrillin-containing microfibrils in several tissues including zonule fibers (Horrigan et al. 1992). MFAP3 is a 41 kDa serine-rich protein localized to zonular microfibrils, found in extracts of developing nuchal ligament, also expressed in fetal aorta and lung (Abrams et al. 1995). MFAP4 is a 29 kDa protein localized to fibrillin-containing microfibrils surrounding elastic fibers in aorta, skin and spleen (Toyoshima et al. 1999).

与弹性纤维相关联的其他蛋白质包括维罗宁蛋白（Dahlback 等人，1989，1990，Hintner 等人，1991）以及一组结构上互不相关的蛋白质，统称为微纤维相关蛋白（MFAPs）（Gibson 等人，1996，2000，Abrams 等人，1995，Toyashima 等人，1999）。这些相互作用的重要性尚未得到充分理解。
维罗宁蛋白存在于血浆、细胞外基质以及血小板α颗粒中。它已被认为是许多过程的调节因子，包括凝血、纤维蛋白溶解、细胞周围蛋白水解、补体依赖性免疫反应、细胞附着和扩散（Zhuang 等人，1996）。它通过精氨酸-甘氨酸-天冬氨酸（RGD）细胞结合序列与整合素αVbeta1（Marshall 等人，1995）、αVbeta3（Pytela 等人，1985）、αVbeta5（Panetti & McKeown Longo，1993）以及αIIbBeta3（Pytela 等人，1986）相互作用。
MFAPs并非结构上相关的家族，而是因其与微纤维的定位而归为一类。MFAP1最初被称为‘相关微纤维蛋白’（AMP）。它是一种54 kDa的蛋白质，经过加工变为32 kDa，定位于包括睫状纤维在内的多种组织中含纤连蛋白的微纤维（Horrigan 等人，1992）。MFAP3是一种41 kDa的富含丝氨酸蛋白，定位于睫状微纤维，可在发育中的颈韧带提取物中发现，亦在胎儿主动脉和肺中表达（Abrams 等人，1995）。MFAP4是一种29 kDa的蛋白质，定位于围绕主动脉、皮肤和脾脏中弹性纤维的含纤连蛋白微纤维（Toyoshima 等人，1999）。