Eshhar N, Hunter C, Wenthold R J, Wada K
Laboratory of Neurochemistry, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892.
FEBS Lett. 1992 Feb 10;297(3):257-62. doi: 10.1016/0014-5793(92)80551-q.
The gene encoding chick kainate-binding protein (c-KBP), a member of the non-NMDA ionotropic glutamate receptor family has been isolated and characterized. The c-KBP gene is at least 13 kilobases long and contains 11 exons interrupted by 10 introns. Primer extension and RNase protection studies identified a major transcription initiation site located 117 bases upstream from the initiation methionine codon ATG. Consensus TATA and CCAAT sequences were detected in the putative promoter region. The structure of the c-KBP gene is strikingly different from that of other members of neurotransmitter-gated ion-channels (cloned at present) although the topology of c-KBP consists of four membrane-spanning domains, a structural characteristic of ionotropic receptor subunits. The c-KBP gene was found to be expressed at high levels in chick cerebellar Bergmann glia and at extremely low levels in the forebrain. The limited expression of the c-KBP gene raises important questions concerning the mechanisms governing the regulation of c-KBP gene transcription.
编码鸡红藻氨酸结合蛋白（c-KBP）的基因已被分离和鉴定，该蛋白是非NMDA离子型谷氨酸受体家族的成员之一。c-KBP基因长度至少为13千碱基，包含11个外显子，被10个内含子隔开。引物延伸和核糖核酸酶保护研究确定了一个主要转录起始位点，位于起始甲硫氨酸密码子ATG上游117个碱基处。在假定的启动子区域检测到共有TATA和CCAAT序列。尽管c-KBP的拓扑结构由四个跨膜结构域组成，这是离子型受体亚基的结构特征，但c-KBP基因的结构与其他神经递质门控离子通道成员（目前已克隆）的结构显著不同。研究发现，c-KBP基因在鸡小脑伯格曼胶质细胞中高水平表达，而在前脑中表达水平极低。c-KBP基因的有限表达引发了关于调控c-KBP基因转录机制的重要问题。
