大鳞副泥鳅β-肌动蛋白基因的cDNA全长克隆及表达分析

为了克隆分析大鳞副泥鳅β-肌动蛋白基因的cDNA序列，并研究该基因的组织表达规律。采用RT-PCR和RACE法，从大鳞副泥鳅（Paramisgurnus dabrymms）肌肉中分离和克隆大鳞副泥鳅β-肌动蛋白基因。结果表明：大鳞副泥鳅β-肌动蛋白基因全长1710bp，其中5’-UTR长73bp，3’-UTR长509bp，编码区长1128bp，编码375个氨基酸。大鳞副泥鳅β-肌动蛋白与其他鱼类氨基酸的同源性大于98％，核苷酸同源性大于87％；系统进化分析表明：大鳞副泥鳅β-肌动蛋白在进化上高度保守；qRT-PCR结果表明：β-肌动蛋白基因在大鳞副泥鳅的肌肉、心、肝、脾、肠、胃、精巢和卵巢共8种组织中都有表达。研究结果不仅为利用β-肌动蛋白基因作为内参基因分析大鳞副泥鳅的基因表达研究提供了序列依据，而且可为大鳞副泥鳅的分子系统学研究提供序列参考。

Cloning and Expression Analysis of β-actin Gene from Paramisgurnus dabryanus

The present experiment was conducted to obtain and analyzed cDNA sequence of β-actin gene from Pararaisgurnus dabryanus, and to study the tissue expression characterization of β-actin mRNA in P. dabryanus. The complete ,β-actin cDNA sequences were obtained from the P. dabryanus muscle tissue using RT-PCR and RACE methods. The complete β-actin cDNA of P. dabryanus was 1710 bp in length, containing an open reading frame of 1128 bp （encoding 375 amino acids）, flanked by 73 bp 5＇UTR and 509 bp 3＇UTR. Sequence analysis indicated that the P. dabryanus β-actin exhibits more than 98% amino acid identity and 87% nucleotide identity with the β-actin of other fishes. Phylogenetic assay indicated that the β-actin gene of P. dabryanus was highly conserved during evolution. Results from quantitative real-time PCR （qRT-PCR） showed the β-actin gene is widely expressed in different organs including skeletal muscle, heart, liver, spleen, intestine, stomach, testis and ovary. The result provided sequence information not only for analyzing gene expression of P. dabryanus using β-actin gene as internal control, but for molecular systematic research of P. dabryanus.