Characterization of a novel cyclic nucleotide-gated channel from zebrafish brain.
Characterization of a novel cyclic nucleotide-gated channel from zebrafish brain.
复制标题
斑马鱼大脑中新型环核苷酸门控通道的表征。
DOI：
10.1016/j.bbrc.2006.07.074
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发表时间：
2006
影响因子：
3.1
通讯作者：
Zimmerman,AnitaL
中科院分区：
文献类型：
--
作者：
Tetreault,MichelleL;Henry,Diane;Horrigan,DianaM;Matthews,Gary;Zimmerman,AnitaL
环核苷酸门控(CNG)通道在视觉和嗅觉的感觉受体中已经有了很好的特征，但在其他组织中的特征仍然很大程度上还不清楚。在这里，我们报告了一种新的斑马鱼脑特异性CNG通道的特征。在CNG通道中独一无二的是，转录本主要在大脑中表达。当在非洲爪哇卵母细胞中表达时，该通道的电生理特性与来自杆状(CNGA1)、嗅觉受体(CNGA2)或锥体(CNGA3)的CNG通道不同。该通道对cAMP的敏感性低于cGMP(K1/2分别为280和7μM)，其最大cAMP效应至少是饱和cGMP时的80%。58pS的单通道电导比大多数其他CNG通道都要大。与其他CNG通道一样，该通道在单价阳离子中相对不具选择性。然而，与其他CNG通道不同的是，在切除斑块后30-100分钟内，宏观电流就开始下降。
Cyclic nucleotide-gated (CNG) channels have been well characterized in the sensory receptors of vision and olfaction, but their characteristics in other tissues remain largely unknown. Here, we report characterization of a novel brain-specific CNG channel from zebrafish. Unique among CNG channels, the transcript is expressed mainly in the brain. When expressed in Xenopus oocytes, the channel’s electrophysiological properties are distinct compared to CNG channels from either rods (CNGA1), olfactory receptors (CNGA2), or cones (CNGA3). The channel is less sensitive to cAMP than cGMP (K1/2of 280 and 7μM, respectively), with a maximum cAMP efficacy at least 80% of that with saturating levels of cGMP. The single-channel conductance of 58pS is larger than most other CNG channels. Like other CNG channels the channel is relatively nonselective among monovalent cations. However, unlike other CNG channels, there was rundown of the macroscopic current within 30–100min after patch excision.