鲶鱼嗅觉神经元中环核苷酸门控通道的分子克隆及单通道特性

Molecular cloning and single-channel properties of the cyclic nucleotide-gated channel from catfish olfactory neurons.

作者信息

Goulding E H, Ngai J, Kramer R H, Colicos S, Axel R, Siegelbaum S A, Chess A

机构信息

Department of Physiology and Cellular Biophysics, College of Physicians and Surgeons, Columbia University, New York, New York 10032.

出版信息

Neuron. 1992 Jan;8(1):45-58. doi: 10.1016/0896-6273(92)90107-o.

DOI:10.1016/0896-6273(92)90107-o

PMID:1370374

Abstract

We have cloned a functional cDNA encoding the cyclic nucleotide-gated channel selectively expressed in catfish olfactory sensory neurons. The cyclic nucleotide-gated channels share sequence and structural features with the family of voltage-gated ion channels. This homology is most evident in transmembrane region S4, the putative voltage sensor domain, and the H5 domain, thought to form the channel pore. We have characterized the single-channel properties of the cloned catfish channel and compared these properties with the channel in native catfish olfactory sensory neurons. The channel is activated equally well by cAMP and cGMP, shows only a slight voltage dependence of gating, and exhibits a pH- and voltage-dependent subconductance state similar to that observed for the voltage-gated L-type calcium channel.

摘要

我们克隆了一个功能性cDNA，其编码在鲶鱼嗅觉感觉神经元中选择性表达的环核苷酸门控通道。环核苷酸门控通道与电压门控离子通道家族具有序列和结构特征。这种同源性在跨膜区域S4（推测的电压传感结构域）和H5结构域最为明显，H5结构域被认为形成通道孔。我们已经对克隆的鲶鱼通道的单通道特性进行了表征，并将这些特性与天然鲶鱼嗅觉感觉神经元中的通道进行了比较。该通道被cAMP和cGMP同等程度地激活，门控仅表现出轻微的电压依赖性，并且呈现出与电压门控L型钙通道所观察到的类似的pH和电压依赖性亚电导状态。