Cell-binding domain of endothelial cell thrombospondin: localization to the 70-kDa core fragment and determination of binding characteristics.
Cell-binding domain of endothelial cell thrombospondin: localization to the 70-kDa core fragment and determination of binding characteristics.
复制标题
内皮细胞血小板反应蛋白的细胞结合域：定位到 70-kDa 核心片段并确定结合特性。
作者：
R. Dardik;J. Lahav
Endothelial and other cell types synthesize thrombospondin (TSP), secrete it into their culture medium, and incorporate it into their extracellular matrix. TSP is a large multifunctional protein capable of specific interactions with other matrix components, as well as with cell surfaces, and can modulate cell adhesion to the extracellular matrix. With the aim of understanding the mechanism by which TSP exerts its effect on cell adhesion, we studied the interaction of endothelial cell TSP (EC-TSP) with three different cell types: endothelial cells, granulosa cells, and myoblasts. We find that endothelial cells specifically bind radiolabeled EC-TSP with a Kd of 25 nM, and the number of binding sites is 2.6 X 10(6)/cell. Binding is not inhibitable by the cell-adhesion peptide GRGDS, indicating that the cell-binding site of EC-TSP is not in the RGD-containing domain. Localization of the cell-binding site was achieved by testing two chymotryptic fragments representing different regions of the TSP molecule, the 70-kDa core fragment and the 27-kDa N-terminal fragment, for their ability to bind to the cells. Cell-binding capacity was demonstrated by the 70-kDa fragment but not by the 27-kDa fragment. Binding of both intact [125I]EC-TSP and of the 125I-labeled 70-kDa fragment was inhibited by unlabeled TSP, heparin, fibronectin (FN), monoclonal anti-TSP antibody directed against the 70-kDa fragment (B7-3), and by full serum, but not by heparin-absorbed serum or the cell-adhesion peptide GRGDS. The 70-kDa fragment binds to endothelial cells with a Kd of 47 nM, and the number of binding sites is 5.0 x 10(6)/cell.(ABSTRACT TRUNCATED AT 250 WORDS)
登录
查看更多内容
DOI：
10.1073/pnas.80.4.998
发表时间：
1983-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
JAFFE, EA;RUGGIERO, JT;MOSHER, DF
通讯作者：
MOSHER, DF
影响因子：
20.3
作者：
E. Jaffe;J. T. Ruggiero;D. Falcone
通讯作者：
E. Jaffe;J. T. Ruggiero;D. Falcone
人类黑素细胞细胞外基质成分的产生和利用。
影响因子：
3.7
作者：
McClenic,BK;Mitra,RS;Riser,BL;Nickoloff,BJ;Dixit,VM;Varani,J
通讯作者：
Varani,J
影响因子：
4.8
作者：
Inae Kim;D. W. Schomberg
通讯作者：
Inae Kim;D. W. Schomberg
血小板反应蛋白与静息和刺激的人血小板的相互作用。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Wolff,R;Plow,EF;Ginsberg,MH
通讯作者：
Ginsberg,MH