美国红鱼生长激素基因的克隆及其遗传进化分析

采用PCR方法从美国红鱼肝脏中扩增出美国红鱼生长激素基因。该基因序列长为1 497 bp,与5个已报道的鲈亚目鱼类生长激素基因结构比较发现,他们的外显子和内含子之比均为6∶5,而且相对应的6个外显子大小一致。用Clustal X软件对美国红鱼和其他13种鲈形目鱼类生长激素基因序列进行比对,选取同源性较高的551 bp的编码区序列构建NJ和MP系统进化树,结果发现由其构建的MP和NJ树与根据形态特征构建的系统发育树基本一致,特别是在鲈形目鱼类科间及科以上分类阶元的系统发育研究方面比较一致。研究结果表明鱼类生长激素基因序列能够较真实反映近缘鱼类之间的关系,是进行鲈形目鱼类系统进化分析的较好遗传标志。

Cloning and Sequencing of the Growth Hormone Gene of Red Drum Sciaenops ocellatus and Its Phylogenetic Significance

Using the specific primers and PCR reaction,the growth hormone(GH) gene of the red drum(Sciaenops ocellatus) was amplified and sequenced.The gene structure was analyzed and compared to the GH genes of 5 other percoid fish downloaded from Genbank.Also the GH gene of the red drum and the genes from 13 Percoidei and 2 Labroidei species were aligned using Clustal X.A matrix of 551 bp was used to construct the phylogenetic tree using maximum parsimony and neighbor-joining methods.Phylogenetic trees by the two methods are identical in most of the clades with high bootstrap support.The results are also identical to those from morphological data.