θ, a novel γ-aminobutyric acid type A receptor subunit
θ, a novel γ-aminobutyric acid type A receptor subunit
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DOI：
10.1073/pnas.96.17.9891
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发表时间：
1999-08-17
影响因子：
11.1
通讯作者：
Whiting, PJ
中科院分区：
文献类型：
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作者：
Bonnert, TP;McKernan, RM;Whiting, PJ
γ-氨基丁酸A型(GABA-A)受体是哺乳动物中枢神经系统抑制性神经传递的主要介质，也是许多临床重要药物的作用部位。这些受体作为一个亚型家族存在，具有不同的时空表达模式和不同的性质，可能是每个亚型的确切作用基础，这个基因家族的最新成员是theta亚基。推导的多肽序列全长627个氨基酸，与pi亚基有最高的同源性(50.5%)。在大鼠纹状体内，这个亚基与α2、pi和y1共同组装，表明伽马氨基丁酸A型受体确实存在，它由AP+伽马、增量或epsilon以外的排列组成。在转基因的哺乳动物细胞中表达α2β1γ1 theta导致受体的形成，与α2β1γ1相比，对γ-氨基丁酸的亲和力降低了4倍。这个亚单位有一个独特的分布，到目前为止的研究表明，在人和猴子大脑的单胺能神经元中都有显著的表达。
gamma-Aminobutyric acid type A (GABA-A) receptors are a major mediator of inhibitory neurotransmission in the mammalian central nervous system, and the site of action of a number of clinically important drugs. These receptors exist as a family of subtypes with distinct temporal and spatial patterns of expression and distinct properties that presumably underlie a precise role for each subtype, The newest member of this gene family is the theta subunit. The deduced polypeptide sequence is 627 amino acids long and has highest sequence identity (50.5%) with the pi subunit. Within the rat striatum, this subunit coassembles with alpha 2, pi, and yl, suggesting that gamma-aminobutyric acid type A receptors consisting of arrangements other than ap + gamma, delta, or epsilon do exist. Expression of alpha 2 beta 1 gamma 1 theta in transfected mammalian cells leads to the formation of receptors with a 4-fold decrease in the affinity for gamma-aminobutyric acid compared with alpha 2 beta 1 gamma 1. This subunit has a unique distribution, with studies so far suggesting significant expression within monoaminergic neurons of both human and monkey brain.