Diab M, Wu J J, Eyre D R
Department of Orthopaedics, University of Washington, Seattle 98195-6500, USA.
Biochem J. 1996 Feb 15;314 ( Pt 1)(Pt 1):327-32. doi: 10.1042/bj3140327.
Type IX collagen, a quantitatively minor collagenous component of cartilage, is known to be associated with and covalently cross-linked to type II collagen fibrils in chick and bovine cartilage. Type IX collagen molecules have also been shown to form covalent cross-links with each other in bovine cartilage. In the present study we demonstrate by structural analysis and location of cross-linking sites that, in human cartilage, type IX collagen is covalently cross-linked to type II collagen and to other molecules of type IX collagen. We also present evidence that, if the proteoglycan form of type IX collagen is present in human cartilage, it can only be a minor component of the matrix, similar to findings with bovine cartilage.
IX型胶原蛋白是软骨中含量较少的胶原成分,已知在鸡和牛的软骨中,它与II型胶原纤维相关联并共价交联。在牛软骨中,IX型胶原蛋白分子也已被证明彼此之间能形成共价交联。在本研究中,我们通过结构分析和交联位点定位证明,在人类软骨中,IX型胶原蛋白与II型胶原蛋白以及其他IX型胶原蛋白分子共价交联。我们还提供了证据表明,如果人类软骨中存在IX型胶原蛋白的蛋白聚糖形式,它也只能是基质中的次要成分,这与牛软骨的研究结果类似。