Bradykinin B2 receptor signaling: structural and functional characterization of the C-terminus.
Bradykinin B2 receptor signaling: structural and functional characterization of the C-terminus.
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缓激肽 B2 受体信号传导：C 末端的结构和功能特征。
DOI：
10.1002/bip.20220
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Mierke,DaleF
中科院分区：
文献类型：
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作者：
Piserchio,Andrea;Zelesky,Veronica;Yu,Jun;Taylor,Linda;Polgar,Peter;Mierke,DaleF
在过去的几年中，细胞内C末端在G蛋白偶联受体（GPCR）信号传导中的重要性变得越来越明显。为了提供生物学功能的结构框架，我们已经确定了缓激肽（BK）B2受体C末端的构象。使用均匀富集15 N-和13 C-的BKB 2受体样品[309-366]，NMR结果清楚地确定了十二烷基磷酸胆碱两性离子表面上的三个α-螺旋。由残基311-326组成的近端螺旋先前基于与视紫红质的同源性建模预测。这对应于通常被称为GPCR的螺旋-8。NMR数据清楚地证实了两个远端螺旋，残基333-345和348-363。通过测定缺乏结构域（缺失突变体）或含有来自相关GPCR、血管紧张素II AT 1a（嵌合体受体）的相应区域的突变体BKB 2受体的信号传导特性（磷酸肌醇形成），探索这些二级结构元件的功能重要性。我们证明了螺旋之间的区域（残基327-333和346-347）可以交换而不损失信号。相比之下，三个螺旋的修饰，特别是含羟基残基，对BKB 2受体的信号传导谱具有显著影响。通过将结构特征与功能数据相结合，开始建立BKB 2受体的信号传导的分子机制。生物聚合物（Pept Sci），2005年
Over the last few years the importance of the intracellular C‐terminus in the signaling of G‐protein coupled receptors (GPCR) has become increasingly evident. In an effort to provide a structural framework for biological function, we have determined the conformation of the C‐terminus of the bradykinin (BK) B2 receptor. Using a uniformly15N‐ and13C‐enriched sample of the BKB2 receptor [309–366], NMR results clearly define three α‐helices lying on the zwitterionic surface of the dodecylphosphocholine. The proximal helix consisting of residues 311–326 was previously predicted based on homology modeling with rhodopsin. This corresponds to what is often called helix‐8 of the GPCRs. The two distal helices, residues 333–345 and 348–363, are clearly borne out by the NMR data. The functional importance of these secondary structural elements was probed by determination of the signaling properties (inositol phosphate formation) of mutant BKB2 receptors lacking the domains (deletion mutants) or containing the corresponding region from the related GPCR, angiotensin II AT1a (chimera receptors). We demonstrate that the regions between the helices (residues 327–333 and 346–347) can be exchanged without loss of signaling. In contrast, modification of the three helices, particularly the hydroxyl‐containing residues, has drastic effects on the signaling profile of the BKB2 receptor. By coupling of the structural features with the functional data, the molecular mechanisms of signaling by the BKB2 receptor are beginning to be established.© 2005 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2005