Nidogen-2:: A new basement membrane protein with diverse binding properties
Nidogen-2:: A new basement membrane protein with diverse binding properties
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DOI：
10.1006/jmbi.1998.2004
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发表时间：
1998-09-11
影响因子：
5.6
通讯作者：
Timpl, R
中科院分区：
文献类型：
--
作者：
Kohfeldt, E;Sasaki, T;Timpl, R
人巢蛋白-2被克隆和测序（1375个残基），并发现共享46%的序列同一性和类似的结构域的安排与以前的特点，基底膜蛋白巢蛋白-1。重组巢蛋白-2纯化为200 kDa的蛋白质从转染的哺乳动物细胞培养基，显示出高水平的N和O-糖基化，并可以清楚地区分巢蛋白-1（150 kDa）的特异性抗体。电子显微镜显示，这两种异构体具有相似的形状，由两条线连接的三个球状结构域组成，但长度略有不同。北方印迹和免疫学分析表明巢蛋白在各种组织和培养细胞中共表达。免疫荧光显示共定位在血管壁和其他基底膜区，但在心脏和骨骼肌的一些差异。巢蛋白-2相互作用：与胶原蛋白I和TV，串珠素在相当的水平巢蛋白-1，但未能结合到纤蛋白。巢蛋白-2与层粘连蛋白-1结合，但仅适度地与层粘连蛋白γ 1链上的表位结合，这促进了巢蛋白-1的hi，oh-亲和结合。两种巢蛋白都是有限数量细胞系的细胞粘附剂，其中巢蛋白-2具有更高的活性。总之，这些数据表明，巢蛋白-1可以补偿一些，但不是所有的功能活动归因于巢蛋白-1。(C)北京：科学出版社.
Human nidogen-2 was cloned and sequenced (1375 residues) and found to share 46% sequence identity and a similar domain arrangement with the previously characterized basement membrane protein nidogen-l. Recombinant nidogen-2 was purified as a 200 kDa protein from transfected mammalian cell medium, showed a high level of N and O-glycosylation, and could be clearly distinguished from nidogen-1 (150 kDa) by specific antibodies. Electron microscopy demonstrated that the two isoforms have a similar shape, consisting of three globular domains connected by two threads, but differ somewhat in length. Northern blots and immunological assays demonstrated co-expression of the nidogens in various tissues and cultured cells. Immunofluoresence revealed colocalization in vessel walls and other basement membrane zones but some differences in heart and skeletal muscle. Nidogen-2 interacted: with collagens I and TV, and perlecan at a comparable level to nidogen-l but failed to bind to fibulins. Nidogen-2 bound to laminin-1, but only moderately to the epitope on the laminin gamma 1 chain, which promotes hi,oh-affinity binding of nidogen-l. Both nidogens were cell-adhesive for a restricted number of cell lines, with nidogen-2 having a higher activity. Together, these data suggest that nidogen-il can compensate for some but not all functional activities ascribed to nidogen-1. (C) 1998 Academic Press.