文章基本信息

标题：Deduced amino acid sequence of a putative sodium channel from the scyphozoan jellyfish Cyanea capillata
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作者：P A Anderson ; M A Holman ; R M Greenberg 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1993
卷号：90
期号：15
页码：7419-7423
DOI：10.1073/pnas.90.15.7419
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Members of the phylum Cnidaria are the lowest extant organisms to possess a nervous system and are the first that are known to contain cells that produce action potentials carried exclusively by Na+ ions. They thus occupy an important position in the evolution of Na+ channels. A cDNA encoding a 198-kDa protein with high sequence identity to known Na+ channels was isolated from the scyphozoan jellyfish Cyanea capillata. The similarity between this and other Na+ channels is greatest in the transmembrane segments and the putative pore region and less so in the cytoplasmic loops that link the four domains of the protein. Phylogenetic analysis of the deduced protein reveals that it is closely related to known Na+ channels, particularly those of squid and Drosophila, and more distantly separated from Ca2+ channels. Scrutiny of the Cyanea channel in regions corresponding to those purported to form the tetrodotoxin receptor and selectivity filter of Na+ channels in higher animals reveals several anomalies that suggest that current models of the location of the tetrodotoxin binding site and Na+ channel selectivity filter are incomplete.