Araki K, Meguro H, Kushiya E, Takayama C, Inoue Y, Mishina M
Department of Neuropharmacology, Niigata University, Japan.
Biochem Biophys Res Commun. 1993 Dec 30;197(3):1267-76. doi: 10.1006/bbrc.1993.2614.
The primary structure of a putative subunit of the mouse glutamate receptor channel, designated as the delta 2 subunit, has been deduced by cloning and sequencing the cDNA. The delta 2 subunit has four putative transmembrane segments characteristic for neurotransmitter-gated ion channels, and shares 56% amino acid sequence identity with the delta 1 subunit of the mouse glutamate receptor channel and 14-24% identity with the subunits of the AMPA-, kainate- or NMDA-selective glutamate receptor channel. RNA blot and in situ hybridization analyses show that the delta 2 subunit mRNA is localized in cerebellar Purkinje cells. Furthermore, immunoblot and immunohistochemical analyses suggest that the delta 2 subunit protein is actually expressed in vivo in Purkinje neurons. The selective localization of the delta 2 subunit in Purkinje cells may imply a role of the delta 2 subunit in Purkinje cell-specific function such as the cerebellar LTD.
通过对cDNA进行克隆和测序，已推导得到小鼠谷氨酸受体通道一个假定亚基（命名为δ2亚基）的一级结构。δ2亚基具有神经递质门控离子通道特有的四个假定跨膜片段，与小鼠谷氨酸受体通道的δ1亚基有56%的氨基酸序列同一性，与AMPA、海人藻酸或NMDA选择性谷氨酸受体通道的亚基有14%-24%的同一性。RNA印迹和原位杂交分析表明，δ2亚基mRNA定位于小脑浦肯野细胞。此外，免疫印迹和免疫组织化学分析提示，δ2亚基蛋白在体内浦肯野神经元中实际表达。δ2亚基在浦肯野细胞中的选择性定位可能暗示其在浦肯野细胞特异性功能（如小脑长时程抑制）中发挥作用。
