Alpha 1-VIII collagen is expressed in the rat glomerulus and in resident glomerular cells.
Alpha 1-VIII collagen is expressed in the rat glomerulus and in resident glomerular cells.
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Alpha 1-VIII 胶原蛋白在大鼠肾小球和常驻肾小球细胞中表达。
DOI：
10.1152/ajprenal.1993.264.6.f1003
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Olsen,BR
中科院分区：
文献类型：
--
作者：
Rosenblum,ND;Briscoe,DM;Karnovsky,MJ;Olsen,BR
目前关于肾小球细胞外基质分子组成的知识并没有解释这些成分是如何相互作用形成稳定的三维结构的。最近人们认识到，短链胶原蛋白如VIII型胶原在一些非肾组织中起着分子桥梁的作用，这增加了这样的分子在肾小球中发挥类似功能的可能性。我们最近发现培养的大鼠肾小球系膜细胞可以合成和分泌多种短链胶原蛋白，其中一种具有类似于α1-VIII型胶原的特性。在本研究中，我们克隆了大鼠肾小球系膜细胞α1-VIII型胶原基因，其序列与小鼠α1-VIII型胶原的同源性为81%。我们利用该基因检测了α1-胶原基因在大鼠肾皮质和培养的肾小球系膜细胞、上皮细胞和内皮细胞中的表达。此外，我们还证明了培养的肾小球系膜细胞可以分泌80 kDa的翻译产物α1-VIII胶原蛋白。免疫细胞化学显示，α1-VIII型胶原定位于正常大鼠肾内大动脉的中层、毛细血管环和系膜。这些结果表明，VIII型胶原是大鼠肾小球和肾内大动脉的正常成分。我们推测，VIII型胶原可能在一定程度上决定了内皮下基质和系膜基质的三维结构。
Current knowledge regarding the molecular composition of extracellular matrices in the glomerulus does not explain how these components interact to form stable three-dimensional structures. The recent recognition that short-chain collagens such as type VIII collagen function as molecular bridges in some nonrenal tissues has raised the possibility that such molecules may serve a similar function in the glomerulus. We have recently shown that cultured rat mesangial cells synthesize and secrete several short-chain collagenous proteins, one of which has properties similar to alpha 1-VIII collagen. In the present study we have isolated a rat mesangial cell alpha 1-VIII collagen cDNA clone, the sequence of which is 81% homologous to mouse alpha 1-VIII collagen. We used this cDNA to determine that alpha 1-VIII collagen mRNA is expressed in rat renal cortex and in cultured glomerular mesangial, epithelial, and endothelial cells. Additionally, we demonstrated that alpha 1-VIII collagen is secreted by cultured mesangial cells as an 80-kDa translation product. By immunocytochemistry, alpha 1-VIII collagen localized to the media of large intrarenal arteries and to the capillary loops and the mesangium of normal rat kidney. These results indicate that type VIII collagen is a normal constituent of the rat glomerulus as well as large intrarenal arteries. We speculate that type VIII collagen may function in part to determine the three-dimensional organization of the subendothelial and mesangial matrices.