McAllister G, Charlesworth A, Snodin C, Beer M S, Noble A J, Middlemiss D N, Iversen L L, Whiting P
Merck Sharp & Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, United Kingdom.
Proc Natl Acad Sci U S A. 1992 Jun 15;89(12):5517-21. doi: 10.1073/pnas.89.12.5517.
Degenerate primers, suitable for polymerase chain reaction studies and based on the conserved structure of G protein-coupled receptors, were used to isolate cDNA clones encoding putative G protein-coupled receptors from a human hippocampal cDNA library. One clone isolated by this approach (AC1) encoded a putative receptor with 39% amino acid sequence identity to the serotonin 5HT1A receptor and 47% identity to the 5HT1D receptor. When expressed transiently in the human embryonic kidney cell line 293, AC1 cDNA-encoded receptor displayed high affinity (Kd = 15 nM) and saturability for [3H]serotonin, suggesting that AC1 encodes a 5HT1-like receptor. However, 5-carboxamidotryptamine demonstrated low affinity (pKi = 5.15) compared with serotonin (pKi = 8.14), consistent with the observed binding of the putative 5HT1E receptor. The excellent correlation observed between the pharmacology of the expressed receptor encoded by AC1 and the human brain 5HT1E binding site confirms that AC1 encodes a 5HT1E receptor and establishes a fifth 5HT1-like receptor subtype.
基于G蛋白偶联受体的保守结构，设计了适用于聚合酶链反应研究的简并引物，用于从人海马cDNA文库中分离编码假定G蛋白偶联受体的cDNA克隆。通过这种方法分离出的一个克隆（AC1）编码一种假定的受体，其氨基酸序列与5-羟色胺5HT1A受体的一致性为39%，与5HT1D受体的一致性为47%。当在人胚肾细胞系293中瞬时表达时，AC1 cDNA编码的受体对[3H]5-羟色胺表现出高亲和力（Kd = 15 nM）和饱和性，表明AC1编码一种5HT1样受体。然而，与5-羟色胺（pKi = 8.14）相比，5-羧基氨基色胺表现出低亲和力（pKi = 5.15），这与假定的5HT1E受体的结合情况一致。在由AC1编码的表达受体的药理学与人类大脑5HT1E结合位点之间观察到的良好相关性，证实AC1编码一种5HT1E受体，并确立了第五种5HT1样受体亚型。
