The Evolution of Calcium Channels

Peter Anderson主题：Re：IBN-9723438摘要电压门控钙通道是一个蛋白质家族，对许多细胞功能至关重要，包括兴奋、收缩、分泌、酶活性和基因调节。它们以多亚单位复合体的形式存在于活细胞中，通常由α1亚基和相关的β、伽马和α2/β亚基组成。孔道形成α1亚基主要负责通道的许多生理和药理特性，根据它们的结构可以分为6个不同的类别。本实验室最近从毛细血管蓝水母中克隆了一个全长的钙通道基因。推测该蛋白的氨基酸序列表明它是L类钙通道家族的成员，这一点得到了它的大部分生理学和药理学的支持。然而，钙通道的整体性质有一些显著的偏差，特别是通道的离子选择性及其对二氢吡啶类钙通道阻滞剂的敏感性。二氢吡啶类钙通道阻滞剂是一种诊断L型钙通道的药物。这项工作的目的是完成对水母钙通道的表征，以期利用该通道的生理和药理异常作为识别L类型通道功能的结构相关性的手段。

Peter Anderson Subject: Re: IBN-9723438 ABSTRACT Voltage gated calcium channels are a family of proteins that are essential for many cell functions, including excitation, contraction, secretion, enzyme activity and gene regulation. They exist in living cells as multisubunit complexes, usually consisting of an alpha1 subunit and associated beta, gamma and alpha2/delta subunits. The pore forming alpha1 subunits, which are primarily responsible for many of the physiological and pharmacological properties of the channels, can be divided on their basis of their structure, into 6 separate classes. A full length calcium channel cDNA was recently cloned from the jellyfish Cyanea capillata, by our lab. The deduced amino acid sequence of this protein suggests that it is a member of the L-type family of calcium channels, and this is supported by much of its physiology and pharmacology. However, there are some significant deviations from the overall properties of calcium channels, in particular the ionic selectivity of the channel and its sensitivity to dihydropyridines, a class of calcium channel blockers that are diagnostics of L-type calcium channels. The aim of the proposed work is to complete the characterization of the jellyfish calcium channel with a view to using the physiological and pharmacological abnormalities of this channel as a means of identifying the structural correlates of L-type channel function.