Molecular evolution of Na^(+) channels in teleost fishes

作     者：Harold H.ZAKON Manda C.JOST Derrick J.ZWICKL Ying LU David M.HILLIS 

作者机构：Section of Neurobiology Section of Integrative BiologyThe University of TexasAustinTXUSA 

出 版 物：《Integrative Zoology》 (整合动物学（英文版）)

年 卷 期：2009年第4卷第1期

页      面：64-74页

核心收录：

学科分类：08[工学] 0824[工学-船舶与海洋工程] 

主　　题：electric fish molecular evolution pufferfish sodium channels tetrodotoxin. 

摘      要：Voltage-dependent sodium channels are critical for electrical *** possess a single sodium channel gene;two rounds of genome duplication early in vertebrates increased the number to *** the teleost-tetrapod split,independent gene duplications in each lineage have further increased the number of sodium channel genes to 10 in tetrapods and 8 in *** we review how the occurrence of multiple sodium channel paralogs has influenced the evolutionary history of three groups of fishes:pufferfish,gymnotiform and mor-myriform electric ***(tetraodontidae)produce a neurotoxin,tetrodotoxin,that binds to and blocks the pore of sodium *** evolved resistance to their own toxins by amino acid substitutions in the pore of their sodium *** substitutions had to occur in parallel across multiple paralogs for organismal re-sistance to *** and mormyriform fishes independently evolved electric organs to generate elec-tricity for communication and object *** sodium channel genes are expressed in muscle in most *** both groups of weakly electric fishes,one gene lost its expression in muscle and became compartmen-talized in the evolutionary novel electric organ,which is a muscle *** gene then evolved at elevated rates,whereas the gene that is still expressed in muscle does not show elevated rates of *** the electric organ-expressing gene,amino acid substitutions occur in parts of the channel involved in determining how long the channel will be open or *** enhanced rate of sequence evolution of this gene likely underlies the spe-cies-level variations in the electric signal.