HKCNMB3 and hKCNMB4, cloning and characterization of two members of the large-conductance calcium-activated potassium channel β subunit family
HKCNMB3 and hKCNMB4, cloning and characterization of two members of the large-conductance calcium-activated potassium channel β subunit family
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DOI：
10.1016/s0014-5793(00)01584-2
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发表时间：
2000-05-26
期刊：
影响因子：
3.5
通讯作者：
Pongs, O
中科院分区：
文献类型：
--
作者：
Behrens, R;Nolting, A;Pongs, O
我们克隆了大电导钙激活钾（BK）通道的两个β亚基，hKCNMB 3（BK β 1）和hKCNMB 4（BK β 4）。mRNA表达谱显示hKCNMB 3在睾丸中表达丰富，hKCNMB 4在脑中表达非常突出。我们在体外CHO细胞中共表达BK通道α（BK α）和BK β 4亚基。我们比较了BK α/β 4介导的电流与平滑肌BK α/β 1通道的电流。BK β 4更显著地减慢激活动力学，导致更陡峭的表观钙敏感性，并将BK电流激活的电压范围移动到比BK β 1更负的电位。BK α/β 4通道不被100 nM的Charybdotoxin或iberiotoxin阻断，并被17 β-雌二醇激活。(C)2000年欧洲生物化学学会联合会。
We cloned two beta subunits of large-conductance calcium-activated potassium (BK) channels, hKCNMB3 (BK beta 1) and hKCNMB4 (BK beta 4). Profiling mRNA expression showed that hKCNMB3 expression is enriched in testis and hKCNMB4 expression is very prominent in brain. We coexpressed BK channel alpha (BK alpha) and BK beta 4 subunits in vitro in CHO cells. We compared BK alpha/beta 4 mediated currents with those of smooth muscle BK alpha/beta 1 channels. BK beta 4 slowed activation kinetics more significantly, led to a steeper apparent calcium sensitivity, and shifted the voltage range of BK current activation to more negative potentials than BK beta 1. BK alpha/beta 4 channels were not blocked by 100 nM charybdotoxin or iberiotoxin, and were activated by 17 beta-estradiol. (C) 2000 Federation of European Biochemical Societies.