A protein kinase C site highly conserved in P2X subunits controls the desensitization kinetics of P2X2 ATP-gated channels
A protein kinase C site highly conserved in P2X subunits controls the desensitization kinetics of P2X2 ATP-gated channels
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DOI：
10.1074/jbc.275.14.10190
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发表时间：
2000-04-07
影响因子：
4.8
通讯作者：
Séguéla, P
中科院分区：
文献类型：
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作者：
Boué-Grabot, É;Archambault, V;Séguéla, P
P2X 受体是由细胞外 ATP 门控的非选择性阳离子通道。重组哺乳动物 P2X 亚基在同聚离子型 ATP 受体中组装，这些受体在异源表达系统中的激动剂敏感性和脱敏率不同。使用非洲爪蟾卵母细胞中的定点诱变和电压钳记录，我们确定了位于 P2X 亚基细胞内 N 末端的高度保守的蛋白激酶 C 位点 TX(K/R) 作为缓慢脱敏（时间常数，>1 分钟）大鼠 P2X(2) 受体、突变受体 P2X(2)T18A、 缺乏该共有位点的 T18N 和 K20T 表现出快速脱敏特性（时间常数、
P2X receptors are nonselective cation channels gated by extracellular ATP. Recombinant mammalian P2X subunits assemble in homomeric ionotropic ATP receptors that differ by their agonist sensitivity and desensitization rate in heterologous expression systems. Using site-directed mutagenesis and voltage clamp recording in Xenopus oocytes, we identified the highly conserved protein kinase C site TX(K/R) located in the intracellular N terminus of P2X subunits as a critical determinant of kinetics in slowly desensitizing (time constant, >1 min) rat P2X(2) receptors, Mutant receptors P2X(2)T18A, T18N, and K20T devoid of this consensus site exhibited quickly desensitizing properties (time constant,