Cannabinoid Receptor Interacting Protein 1a Competition with β-Arrestin for CB1 Receptor Binding Sites
Cannabinoid Receptor Interacting Protein 1a Competition with β-Arrestin for CB1 Receptor Binding Sites
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大麻素受体相互作用蛋白 1a 与 β-Arrestin 竞争 CB1 受体结合位点
作者：
Lawrence C. Blume;Theresa Patten;Khalil Eldeeb;S. Leone‐Kabler;Alexander A. Ilyasov;Bradley M Keegan;Jeremy E. O’Neal;C. Bass;R. Hantgan;W. Lowther;D. Selley;A. Howlett
大麻素受体相互作用蛋白1a(CRIP1a)是一种CB1受体(CB1R)C末端相关蛋白，可改变CB1R与G蛋白的相互作用。我们测试了这样的假设，即CRIP1a也能够改变CB1R与β-arrestin蛋白的相互作用，这些蛋白质在C末端与CB1R相互作用。免疫共沉淀研究表明，CB1R与CRIP1a或β-arrestin形成复合物，但CRIP1a和β-arrestin不能相互免疫共沉淀。这表明竞争CRIP1a和β-arrestin与CB1R结合，我们假设这可能会减弱β-arrestin介导CB1R内化的作用。我们确定，激动剂介导的内源性表达的CB1R细胞表面密度的降低是依赖于笼蛋白和动力素的，并且可以被模拟为激动剂诱导瞬时表达的GFP-CB1R的聚集。CRIP1a的过表达减弱了CP55940介导的GFP-CB1R和内源性β-arrestin在点状细胞上的重分布，反之，CRIP1a基因敲除增强了β-arrestin在点状细胞上的重分布。模拟CB1R C末端的多肽既能与细胞提取物中的CRIP1a结合，也能与纯化的重组CRIP1a结合。亲和力下拉研究表明，CB1R远端C-末端14-肽的苏氨酸-468位的磷酸化降低了CB1R-CRIP1a的结合。免疫共沉淀结果表明，C1R蛋白复合体的中心或远端C端肽竞争Cb1R与CRIP1a的结合，而磷酸化的中心C端肽竞争与β-arrestin 1的结合，而磷酸化的中心或远端C端多肽竞争与β-arrestin 2的结合。因此，CRIP1a可以与β-arrestins竞争与C端的CB1R结构域的相互作用，这可能影响激动剂驱动的β-arrestin介导的CB1R的内化。
Cannabinoid receptor interacting protein 1a (CRIP1a) is a CB1 receptor (CB1R) distal C-terminal-associated protein that alters CB1R interactions with G-proteins. We tested the hypothesis that CRIP1a is capable of also altering CB1R interactions with β-arrestin proteins that interact with the CB1R at the C-terminus. Coimmunoprecipitation studies indicated that CB1R associates in complexes with either CRIP1a or β-arrestin, but CRIP1a and β-arrestin fail to coimmunoprecipitate with each other. This suggests a competition for CRIP1a and β-arrestin binding to the CB1R, which we hypothesized could attenuate the action of β-arrestin to mediate CB1R internalization. We determined that agonist-mediated reduction of the density of cell surface endogenously expressed CB1Rs was clathrin and dynamin dependent and could be modeled as agonist-induced aggregation of transiently expressed GFP-CB1R. CRIP1a overexpression attenuated CP55940-mediated GFP-CB1R as well as endogenous β-arrestin redistribution to punctae, and conversely, CRIP1a knockdown augmented β-arrestin redistribution to punctae. Peptides mimicking the CB1R C-terminus could bind to both CRIP1a in cell extracts as well as purified recombinant CRIP1a. Affinity pull-down studies revealed that phosphorylation at threonine-468 of a CB1R distal C-terminus 14-mer peptide reduced CB1R-CRIP1a association. Coimmunoprecipitation of CB1R protein complexes demonstrated that central or distal C-terminal peptides competed for the CB1R association with CRIP1a, but that a phosphorylated central C-terminal peptide competed for association with β-arrestin 1, and phosphorylated central or distal C-terminal peptides competed for association with β-arrestin 2. Thus, CRIP1a can compete with β-arrestins for interaction with C-terminal CB1R domains that could affect agonist-driven, β-arrestin-mediated internalization of the CB1R.
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影响因子：
--
作者：
F. Tanious;Binh Nguyen;W. Wilson
通讯作者：
F. Tanious;Binh Nguyen;W. Wilson
M2 和 M4 毒蕈碱乙酰胆碱受体的内化涉及小 G 蛋白的不同子集。
影响因子：
6.1
作者：
Reiner,Cindy;Nathanson,NeilM
通讯作者：
Nathanson,NeilM
影响因子：
11.8
作者：
Macia, Eric;Ehrlich, Marcelo;Kirchhausen, Tomas
通讯作者：
Kirchhausen, Tomas
针对 m4 和 m5 毒蕈碱胆碱能受体选择性抗血清的开发：大鼠脑中 m4 和 m5 受体的分布。
影响因子：
3.6
作者：
Yasuda,RP;Ciesla,W;Flores,LR;Wall,SJ;Li,M;Satkus,SA;Weisstein,JS;Spagnola,BV;Wolfe,BB
通讯作者：
Wolfe,BB
影响因子：
64.8
作者：
Kang Y;Zhou XE;Gao X;He Y;Liu W;Ishchenko A;Barty A;White TA;Yefanov O;Han GW;Xu Q;de Waal PW;Ke J;Tan MH;Zhang C;Moeller A;West GM;Pascal BD;Van Eps N;Caro LN;Vishnivetskiy SA;Lee RJ;Suino-Powell KM;Gu X;Pal K;Ma J;Zhi X;Boutet S;Williams GJ;Messerschmidt M;Gati C;Zatsepin NA;Wang D;James D;Basu S;Roy-Chowdhury S;Conrad CE;Coe J;Liu H;Lisova S;Kupitz C;Grotjohann I;Fromme R;Jiang Y;Tan M;Yang H;Li J;Wang M;Zheng Z;Li D;Howe N;Zhao Y;Standfuss J;Diederichs K;Dong Y;Potter CS;Carragher B;Caffrey M;Jiang H;Chapman HN;Spence JC;Fromme P;Weierstall U;Ernst OP;Katritch V;Gurevich VV;Griffin PR;Hubbell WL;Stevens RC;Cherezov V;Melcher K;Xu HE
通讯作者：
Xu HE