Interaction of discoidin domain receptor 1 with collagen type 1
Interaction of discoidin domain receptor 1 with collagen type 1
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DOI：
10.1016/j.jmb.2006.12.073
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发表时间：
2007-03-23
影响因子：
5.6
通讯作者：
Iscru, Daniel F.
中科院分区：
文献类型：
--
作者：
Agarwal, Gunjan;Mihai, Cosmin;Iscru, Daniel F.
盘状结构域受体1（DDR 1）是广泛表达的酪氨酸激酶受体，其结合至胶原蛋白（包括1型胶原蛋白）并被其激活。关于DDR 1与胶原蛋白的相互作用及其可能的功能意义知之甚少。在这里，我们阐明的DDR 1胞外结构域（ECD）的1型胶原蛋白的结合模式及其对胶原纤维的影响。我们的体外测定利用DDR 1-Fc融合蛋白，其仅含有DDR 1的ECD。使用表面等离子体共振，我们证实了DDR 1-Fc的进一步寡聚化（通过抗Fc抗体）大大增强了其与固定的胶原1型的结合。通过原子力显微镜的单分子成像显示，DDR 1寡聚体结合在重叠或相邻的胶原蛋白分子，几乎不存在于孤立的胶原蛋白分子。发现DDR 1寡聚物与胶原蛋白的相互作用在体外和基于细胞的测定中均调节胶原蛋白原纤维形成。DDR 1存在下形成的胶原纤维平均直径更大，交联程度更高，并且缺乏天然带状结构。DDR 1 ECD的存在导致胶原蛋白分子在体外和过表达DDRI的细胞表面“锁定”在不完全的纤维状态。我们的研究结果表明，一个重要的功能作用的DDR 1 ECD，这发生在激酶死亡的DDR 1亚型和脱落的可溶性蛋白质自然。通过DDR 1 ECD对胶原原纤维形成的调节阐明了通过DDR 1调节胶原的新机制。(c)2007爱思唯尔有限公司保留所有权利。
Discoidin domain receptor 1 (DDR1) is a widely expressed tyrosine kinase receptor which binds to and gets activated by collagens including collagen type 1. Little is understood about the interaction of DDR1 with collagen and its possible functional implications. Here, we elucidate the binding pattern of the DDR1 extracellular domain (ECD) to collagen type 1 and its impact on collagen fibrillogenesis. Our in vitro assays utilized DDR1-Fc fusion proteins, which contain only the ECD of DDR1. Using surface plasmon resonance, we confirmed that further oligomerization of DDR1-Fc (by means of anti-Fc antibody) greatly enhances its binding to immobilized collagen type 1. Single-molecule imaging by means of atomic force microscopy revealed that DDR1 oligomers bound at overlapping or adjacent collagen molecules and were nearly absent on isolated collagen molecules. Interaction of DDR1 oligomers with collagen was found to modulate collagen fibrillogenesis both in vitro and in cell-based assays. Collagen fibers formed in the presence of DDR1 had a larger average diameter, were more cross-linked and lacked the native banded structure. The presence of DDR1 ECD resulted in "locking" of collagen molecules in an incomplete fibrillar state both in vitro and on surfaces of cells overexpressing DDRI. Our results signify an important functional role of the DDR1 ECD, which occurs naturally in kinase-dead isoforms of DDR1 and as a shedded soluble protein. The modulation of collagen fibrillogenesis by the DDR1 ECD elucidates a novel mechanism of collagen regulation by DDR1. (c) 2007 Elsevier Ltd. All rights reserved.