CHARACTERIZATION OF A MAMMALIAN CDNA FOR AN INACTIVATING VOLTAGE-SENSITIVE K+ CHANNEL
CHARACTERIZATION OF A MAMMALIAN CDNA FOR AN INACTIVATING VOLTAGE-SENSITIVE K+ CHANNEL
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DOI：
10.1016/0896-6273(91)90299-f
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发表时间：
1991-09-01
期刊：
影响因子：
16.2
通讯作者：
JAN, LY
中科院分区：
文献类型：
--
作者：
BALDWIN, TJ;TSAUR, ML;JAN, LY
从大鼠海马区分离到一个编码K+通道多肽的基因，其氨基酸序列与果蝇Shal的同源性为72%。该基因在非洲爪哇卵母细胞中的功能性表达产生了4-氨基-吡啶敏感的K+通道，表现出快速的失活动力学。通过缺失氨基末端的3个碱性残基，使失活最快的成分减慢。Northern杂交显示，编码这种K+通道多肽的mRNA在大脑和心脏中的表达水平相似。原位杂交显示，编码该K+通道的mRNA主要集中在脑内的海马区、齿状回和缰核。因此，这种K+通道多肽很可能形成一些在哺乳动物神经系统和心脏中表达的A型K+通道。
A cDNA clone encoding a K+ channel polypeptide with 72% amino acid sequence identity to Drosophila Shal was isolated from rat hippocampus. Functional expression of the cDNA in Xenopus oocytes generated 4-amino-pyridine-sensitive K+ channels displaying rapid inactivation kinetics. The fastest component of inactivation was slowed by the deletion of 3 basic residues in the aminoterminal region. Northern blots revealed that the mRNA encoding this K+ channel polypeptide was expressed at a similar level in the brain and in the heart. In situ hybridization revealed that the mRNA encoding this K+ channel appeared concentrated in the hippocampus, dentate gyrus, and habenular nucleus in the brain. Thus, this K+ channel polypeptide is likely to form some of the A-type K+ channels expressed in the mammalian nervous system and heart.