Purification and structural characterization of transforming growth factor beta induced protein (TGFBIp) from porcine and human corneas
Purification and structural characterization of transforming growth factor beta induced protein (TGFBIp) from porcine and human corneas
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DOI：
10.1021/bi048589s
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发表时间：
2004-12-28
期刊：
影响因子：
2.9
通讯作者：
Enghild, JJ
中科院分区：
文献类型：
--
作者：
Andersen, RB;Karring, H;Enghild, JJ
编码转化生长因子β诱导蛋白（TGF β 1 β）的TGFBI（BIGH 3）基因突变是几种表型不同的角膜营养不良的原因。虽然这些蛋白质错误折叠疾病的遗传学是有据可查的，但对这种细胞外基质蛋白本身知之甚少。在这项研究中，我们已经纯化的TGF β 1 β从正常的人和猪角膜使用非变性条件和标准的色谱技术。这两个同系物被证明是单体，我们没有发现翻译后添加的证据。人和猪TGF β 1 β的C末端主要在整联蛋白结合序列Arg（642）-Gly（643）-ASP（644）（RGD）之后截短。然而，使用针对C-末端片段（残基648-683）的抗体，我们还在角膜提取物中检测到少量全长TGF β 1。在人和猪角膜中，大约60%的TGF β 1 β通过二硫键与细胞外基质的不溶性组分共价结合。
Mutations in the TGFBI (BIGH3) gene that encodes for transforming growth factor beta induced protein (TGFBIp) are the cause of several phenotypically different corneal dystrophies. While the genetics of these protein misfolding diseases are well documented, relatively little is known about this extracellular matrix protein itself. In this study, we have purified TGFBIp from normal human and porcine corneas using nondenaturing conditions and standard chromatography techniques. The two homologues were shown to be monomers, and we did not find evidence for posttranslational additions. The C-terminal of both human and porcine TGFBIp is truncated predominantly after the integrin binding sequence Arg(642)-Gly(643)-ASP(644) (RGD). However, using an antibody against the C-terminal fragment (residues 648-683), we also detected a small amount of full-length TGFBIp in corneal extracts. Approximately 60% of TGFBIp was covalently associated with insoluble components of the extracellular matrix in both human and porcine corneas through a disulfide bridge.