Crystal Structure of p44, a Constitutively Active Splice Variant of Visual Arrestin
Crystal Structure of p44, a Constitutively Active Splice Variant of Visual Arrestin
复制标题
DOI：
10.1016/j.jmb.2012.01.028
复制
发表时间：
2012-03-09
影响因子：
5.6
通讯作者：
Batra-Safferling, Renu
中科院分区：
文献类型：
--
作者：
Granzin, Joachim;Cousin, Anneliese;Batra-Safferling, Renu
视觉抑制蛋白特异性结合光活化和磷酸化的视紫红质并使光转导失活。相反，p44剪接变体可以通过结合非磷酸化的光激活视紫红质来终止光转导。在这里，我们报告的晶体结构的牛p44在1.85埃的分辨率。与天然arrestin相比，p44结构揭示了对受体结合至关重要的区域，即柔性环V-VI和极性核心区域的显著差异。另外，静电势在N-结构域和C-结构域上是显著正的。p44结构代表了一种活性构象，可作为解释抑制蛋白变体中发现的“组成型活性”的模型。(C)2012爱思唯尔有限公司保留所有权利。
Visual arrestin specifically binds to photoactivated and phosphorylated rhodopsin and inactivates phototransduction. In contrast, the p44 splice variant can terminate phototransduction by binding to nonphosphorylated light-activated rhodopsin. Here we report the crystal structure of bovine p44 at a resolution of 1.85 angstrom. Compared to native arrestin, the p44 structure reveals significant differences in regions crucial for receptor binding, namely flexible loop V-VI and polar core regions. Additionally, electrostatic potential is remarkably positive on the N-domain and the C-domain. The p44 structure represents an active conformation that serves as a model to explain the 'constitutive activity' found in arrestin variants. (C) 2012 Elsevier Ltd. All rights reserved.