Julius D, Huang K N, Livelli T J, Axel R, Jessell T M
Department of Biochemistry and Molecular Biophysics, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Proc Natl Acad Sci U S A. 1990 Feb;87(3):928-32. doi: 10.1073/pnas.87.3.928.
Serotonin exerts its diverse physiological effects by interacting with multiple distinct receptor subtypes. We have isolated a rat brain 5HT2 serotonin receptor cDNA by virtue of its homology with the 5HT1c receptor. The 5HT2 receptor is a member of the family of receptors that are linked to guanine nucleotide-binding proteins and are predicted to span the lipid bilayer seven times. Overall sequence identity between the 5HT2 and 5HT1c receptors is 49%, but identity within the transmembrane domains is 80%. Expression of both the 5HT2 and 5HT1c receptors in transfected mouse fibroblasts activates phospholipase C signaling pathways and promotes cellular transformation. However, RNA blotting shows that these two receptor subtypes are differentially expressed in the central nervous system. In this manner, structurally and functionally homologous receptor subtypes may elicit distinct physiologic actions.
血清素通过与多种不同的受体亚型相互作用发挥其多样的生理效应。我们凭借与5HT1c受体的同源性分离出了大鼠脑5HT2血清素受体cDNA。5HT2受体是与鸟嘌呤核苷酸结合蛋白相连且预计跨脂质双层七次的受体家族成员。5HT2和5HT1c受体之间的总体序列同一性为49%，但跨膜结构域内的同一性为80%。5HT2和5HT1c受体在转染的小鼠成纤维细胞中的表达均激活磷脂酶C信号通路并促进细胞转化。然而，RNA印迹显示这两种受体亚型在中枢神经系统中差异表达。通过这种方式，结构和功能同源的受体亚型可能引发不同的生理作用。
