An RGD sequence in the P2Y(2) receptor interacts with alpha(V)beta(3) integrins and is required for G(o)-mediated signal transduction.
An RGD sequence in the P2Y(2) receptor interacts with alpha(V)beta(3) integrins and is required for G(o)-mediated signal transduction.
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DOI：
10.1083/jcb.153.3.491
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发表时间：
2001-04-30
期刊：
影响因子：
--
通讯作者：
Weisman GA
中科院分区：
文献类型：
--
作者：
Erb L;Liu J;Ockerhausen J;Kong Q;Garrad RC;Griffin K;Neal C;Krugh B;Santiago-Pérez LI;González FA;Gresham HD;Turner JT;Weisman GA
P2Y2 核苷酸受体 (P2Y2R) 在其第一个细胞外环中包含整合素结合域精氨酸-甘氨酸-天冬氨酸 (RGD)，这提高了这种 G 蛋白偶联受体直接与整合素相互作用的可能性。对应于 P2Y2R 第一个细胞外环的肽与 K562 红白血病细胞的结合受到针对 αVβ3/β5 整联蛋白和整联蛋白相关血小板反应蛋白受体 CD47 的抗体的抑制。用表位标记的 P2Y2R 转染的细胞的免疫荧光表明，αV 整联蛋白与野生型 P2Y2R 的共定位比与 RGD 序列被 RGE 替换的突变型 P2Y2R 的共定位好 10 倍。与野生型 P2Y2R 相比，RGE 突变体需要高 1,000 倍的激动剂浓度来磷酸化粘着斑激酶、激活细胞外信号调节激酶并启动 PLC 依赖性细胞内 Ca2+ 动员。此外，抗αV整联蛋白抗体部分抑制了野生型P2Y2R介导的这些信号传导事件。百日咳毒素（Gi/o 蛋白的抑制剂）部分抑制野生型 P2Y2R 介导的 Ca2+ 动员，但不抑制 RGE 突变体介导的 Ca2+ 动员，表明 P2Y2R 介导的 Go 激活需要 RGD 序列，但 Gq 不需要。由于 CD47 已被证明与 Gi/o 家族蛋白直接相关，因此这些结果表明 P2Y2R、整联蛋白和 CD47 之间的相互作用对于 P2Y2R 与 Go 的偶联可能很重要。
The P2Y2 nucleotide receptor (P2Y2R) contains the integrin-binding domain arginine-glycine-aspartic acid (RGD) in its first extracellular loop, raising the possibility that this G protein–coupled receptor interacts directly with an integrin. Binding of a peptide corresponding to the first extracellular loop of the P2Y2R to K562 erythroleukemia cells was inhibited by antibodies against αVβ3/β5 integrins and the integrin-associated thrombospondin receptor, CD47. Immunofluorescence of cells transfected with epitope-tagged P2Y2Rs indicated that αV integrins colocalized 10-fold better with the wild-type P2Y2R than with a mutant P2Y2R in which the RGD sequence was replaced with RGE. Compared with the wild-type P2Y2R, the RGE mutant required 1,000-fold higher agonist concentrations to phosphorylate focal adhesion kinase, activate extracellular signal–regulated kinases, and initiate the PLC-dependent mobilization of intracellular Ca2+. Furthermore, an anti-αV integrin antibody partially inhibited these signaling events mediated by the wild-type P2Y2R. Pertussis toxin, an inhibitor of Gi/o proteins, partially inhibited Ca2+ mobilization mediated by the wild-type P2Y2R, but not by the RGE mutant, suggesting that the RGD sequence is required for P2Y2R-mediated activation of Go, but not Gq. Since CD47 has been shown to associate directly with Gi/o family proteins, these results suggest that interactions between P2Y2Rs, integrins, and CD47 may be important for coupling the P2Y2R to Go.
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DOI：
10.1083/jcb.135.2.533
发表时间：
1996-10
期刊：
The Journal of cell biology
影响因子：
--
作者：
Gao AG;Lindberg FP;Dimitry JM;Brown EJ;Frazier WA
通讯作者：
Frazier WA
影响因子：
4.8
作者：
Frazier, WA;Gao, AG;Linder, ME
通讯作者：
Linder, ME
影响因子：
7.8
作者：
Lindberg, FP;Gresham, HD;Brown, EJ
通讯作者：
Brown, EJ
影响因子：
64.5
作者：
BROOKS, PC;MONTGOMERY, AMP;CHERESH, DA
通讯作者：
CHERESH, DA
影响因子：
56.9
作者：
BROOKS, PC;CLARK, RAF;CHERESH, DA
通讯作者：
CHERESH, DA