鳜传染性脾肾坏死病毒p31基因结构及序列分析

Characterization of the p31 gene of infectious spleen and kidney necrosis virus of Siniperca chuatsi

报道了鳜传染性脾肾坏死病毒 (ISKNV)的p31基因结构及其序列分析。对ISKNVDNAHindIIIE酶切片段的序列分析结果发现该序列中含有完整的p31基因。ISKNVp31基因完整读码框为 6 75bp ,GC含量为 4 9.78% ,等电点为 7.6 1,编码一个长为 2 2 5aa、分子量为 2 5 .3kD的推定蛋白。结构分析发现该基因具有启动子元件TATAbox和CAATmotif,下游有反向重复序列可形成茎环 ,另外还有一段直接重复序列和二联体结构。ISKNV与其它 3种虹彩病毒 (包括FV3、LCDV - 1和EHNV)的p31基因氨基酸序列具有一定的同源性 ,但ISKNV与它们的同源性不高 。

P31 gene of infectious spleen and kidney necrosis virus(ISKNV)of Siniperca chuatsi had been sequenced. The open reading frame of the gene is 675 nucleotides long, encoding a putative protein of 225 amino acids with 25.3kD. The 5' noncoding region has a TATA box and CAAT motif. A stem loop, a direct repeat sequence and a short dyad are contained downstream of the translation stop codon. The results of comparison of the homology with other iridoviruses p31 genes showed that ISKNV p31 gene has lower identities with others. Alignment of amino acid sequences and a phylogenetic tree of p31 genes of four iridoviruses have been constructed. The results indicated that ISKNV is different from the viruses of the genus Ranavirus and Lymphocystivirus.