Functional expression of an inactivating potassium channel cloned from human heart.
Functional expression of an inactivating potassium channel cloned from human heart.
复制标题
从人心脏克隆的失活钾通道的功能表达。
DOI：
10.1161/01.res.71.3.732
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发表时间：
1992
影响因子：
20.1
通讯作者：
Bennett,PB
中科院分区：
文献类型：
--
作者：
Po,S;Snyders,DJ;Baker,R;Tamkun,MM;Bennett,PB
最近，从人心室心肌中克隆了一个与钾离子通道Shaker家族同源的K+通道。然而，证明cDNA编码K+通道需要适当的翻译和表达功能性离子选择通道。因此，通过细胞质注射体外转录的cRNA到非洲爪蟾卵母细胞中，并通过双电极电压钳法筛选，试图表达这一推测的人类K+通道DNA。这导致表达的电压门控通道迅速失活（失活时间常数为47.6 +/- 3.6 msec; 0 mV; n = 10），并且对K+的选择性至少是Na+的50倍（Na+/K+渗透率比为0.02）。这些通道表现出电压依赖性激活（半最大电压，-34 +/- 0.7 mV, n = 5），当膜电位夹紧在-60 mV附近（半最大电压，-62 +/- 7 mV, n = 10）时，50%的通道在2秒内失活。表达的蛋白产生的K+电流具有许多性质，类似于在天然心肌细胞中观察到的心脏瞬时外向电流的4-氨基吡啶敏感钙不敏感成分，因此可能作为该电流的一种分子底物。
Recently a putative K+ channel with homology to the Shaker family of potassium channels has been cloned from human ventricular myocardium. However, proof that the cDNA encodes a K+ channel requires appropriate translation and expression of a functional ion-selective channel. Therefore, expression of this putative human K+ channel DNA was attempted by cytoplasmic injections of in vitro transcribed cRNA into Xenopus laevis oocytes and screening by two-electrode voltage-clamp methods. This resulted in expression of voltage-gated channels that rapidly inactivated (time constant of inactivation, 47.6 +/- 3.6 msec; 0 mV; n = 10) and were at least 50 times more selective for K+ than Na+ (Na+/K+ permeability ratio of 0.02). The channels showed voltage-dependent activation (half-maximal voltage, -34 +/- 0.7 mV; n = 5), and 50% of the channels were inactivated within 2 seconds when the membrane potential was clamped near -60 mV (half-maximal voltage, -62 +/- 7 mV; n = 10). The expressed protein resulted in a K+ current that had many properties similar to the 4-aminopyridine-sensitive calcium-insensitive component of the cardiac transient outward current that is observed in native cardiac myocytes and thus may serve as one molecular substrate for this current.
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DOI：
10.1016/s0021-9258(18)60827-0
发表时间：
1987
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
V. Pribluda;H. Metzger
通讯作者：
H. Metzger
影响因子：
3.4
作者：
G. K. Smelser;S. Silver
通讯作者：
S. Silver
豚鼠大脑皮质制剂中肌醇磷酸盐和环 AMP 的积累。
DOI：
--
发表时间：
1985
期刊：
Biochimica et Biophysica Acta
影响因子：
--
作者：
E. Hollingsworth;J. Daly
通讯作者：
J. Daly
表皮生长因子刺激 A431 细胞中肌醇 (1,4,5)-三磷酸的快速积累以及从细胞内储存动员的胞质钙的增加。
DOI：
--
发表时间：
1987
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Hepler,JR;Nakahata,N;Lovenberg,TW;DiGuiseppi,J;Herman,B;Earp,HS;Harden,TK
通讯作者：
Harden,TK
静脉输注组胺5-羟色胺、缓激肽和前列腺素对眼压的影响。
DOI：
10.1016/s0014-4835(80)80057-1
发表时间：
1974
影响因子：
--
作者：
Chiang Ts
通讯作者：
Chiang Ts