Differential sensitivity of types 1 and 2 cholecystokinin receptors to membrane cholesterol
Differential sensitivity of types 1 and 2 cholecystokinin receptors to membrane cholesterol
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DOI：
10.1194/jlr.m020065
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发表时间：
2012-01-01
影响因子：
6.5
通讯作者：
Miller, Laurence J.
中科院分区：
文献类型：
--
作者：
Potter, Ross M.;Harikumar, Kaleeckal G.;Miller, Laurence J.
最近的研究表明，膜胆固醇可以与G蛋白偶联受体（GPCRs），并影响其功能。以前，我们报道，操纵膜胆固醇影响配体结合和信号转导的1型胆囊收缩素受体（CCK 1 R），A类GPCR。我们现在证明，密切相关的2型胆囊收缩素受体（CCK 2 R）不共享这种胆固醇敏感性。这两种受体的序列揭示了几乎相同的胆固醇相互作用基序在类似的位置在跨膜段2，3，4，和5。这些受体之间的胆固醇敏感性的差异，尽管它们的结构关系密切，提供了一个独特的机会，以确定可能的结构基础的胆固醇敏感性的CCK 1 R。为了评估CCK 1 R不同区域对胆固醇敏感性的相对贡献，我们进行了配体结合研究和生物活性测定野生型和CCK 2 R/CCK 1 R嵌合受体携带中国仓鼠卵巢细胞膜胆固醇操作后。我们还将这些研究扩展到胆固醇相互作用基序内的定点突变。这些结果有助于更好地理解CCK 1 R中胆固醇敏感性的结构要求，并深入了解其他胆固醇敏感性A类GPCR的功能。波特，R.M.，K.G. Harikumar，S. V. Wu，and L. J.米勒. 1型和2型胆囊收缩素受体对膜胆固醇的敏感性差异。《脂类研究杂志》，2012年。53：137-148。
Recent studies indicate that membrane cholesterol can associate with G protein-coupled receptors (GPCRs) and affect their function. Previously, we reported that manipulation of membrane cholesterol affects ligand binding and signal transduction of the type 1 cholecystokinin receptor (CCK1R), a Class A GPCR. We now demonstrate that the closely related type 2 cholecystokinin receptor (CCK2R) does not share this cholesterol sensitivity. The sequences of both receptors reveal almost identical cholesterol interaction motifs in analogous locations in transmembrane segments two, three, four, and five. The disparity in cholesterol sensitivity between these receptors, despite their close structural relationship, provides a unique opportunity to define the possible structural basis of cholesterol sensitivity of CCK1R. To evaluate the relative contributions of different regions of CCK1R to cholesterol sensitivity, we performed ligand binding studies and biological activity assays of wildtype and CCK2R/CCK1R chimeric receptor-bearing Chinese hamster ovary cells after manipulation of membrane cholesterol. We also extended these studies to site-directed mutations within the cholesterol interaction motifs. The results contribute to a better understanding of the structural requirements for cholesterol sensitivity in CCK1R and provides insight into the function of other cholesterol-sensitive Class A GPCRs.-Potter, R.M., K.G. Harikumar, S.V. Wu, and L.J. Miller. Differential sensitivity of types 1 and 2 cholecystokinin receptors to membrane cholesterol. J. Lipid Res. 2012. 53: 137-148.