Single-channel properties and pH sensitivity of two-pore domain K+ channels of the TALK family
Single-channel properties and pH sensitivity of two-pore domain K+ channels of the TALK family
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DOI：
10.1016/j.bbrc.2004.01.137
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发表时间：
2004-03-19
影响因子：
3.1
通讯作者：
Kim, D
中科院分区：
文献类型：
--
作者：
Kang, DW;Kim, D
双孔K-2 P通道家族包括TALK、TREK、TWIK、TRESK、TALK和THIK亚家族，并且TALK-1、TALK-2和TALK-2是TALK亚家族的功能成员。在这里，我们首次报道了TALK-2的单通道特性及其pH（0）敏感性，并将其与TALK-1和ASK-2进行了比较。在转染的COS-7细胞中，三个TALK K-2 P通道可以很容易地通过它们在单通道电导和门控动力学上的差异来识别。在对称的150 mM KCl中，TALK-1、TALK-2和ASK-2的单通道电导分别为21、33和70 pS（~ 60 mV）。TALK-2主要对碱性范围（pH 7-10）敏感，而TALK- 1和ASK-2对更宽的pH范围（6-10）敏感。pH值的变化主要影响开放频率。因此，在天然组织中表达的TALK家族的成员可以基于它们的单通道动力学和pH敏感性来鉴定。(C)2004年爱思唯尔公司All rights reserved.
The two-pore K-2P channel family comprises TASK, TREK, TWIK, TRESK, TALK, and THIK subfamilies, and TALK-1, TALK-2, and TASK-2 are functional members of the TALK subfamily. Here we report for the first time the single-channel properties of TALK-2 and its pH(0) sensitivity, and compare them to those of TALK-1 and TASK-2. In transfected COS-7 cells, the three TALK K-2P channels could be identified easily by their differences in single-channel conductance and gating kinetics. The single-channel conductances of TALK-1, TALk-2, and TASK-2 in symmetrical 150mM KCl were 21, 33, and 70 pS (-60mV), respectively. TALK-2 was sensitive mainly to the alkaline range (pH 7-10), whereas TALK- 1 and TASK-2 were sensitive to a wider pH,, range (6-10). The effect of pH changes was mainly on the opening frequency. Thus, members of the TALK family expressed in native tissues may be identified based on their single-channel kinetics and pH. sensitivity. (C) 2004 Elsevier Inc. All rights reserved.