传染性造血器官坏死病毒毒株核蛋白基因片段的克隆及序列分析

利用RTG～2细胞对传染性造血器官坏死病毒（IHNV）的敏感性对IHNV-DL进行扩增，采用TR—Izol法提取病毒RNA，用IHNV核蛋白基因的一对通用引物进行RT-PCR扩增，将扩增出的一条786bp的基因纯化、克隆至pMD18－T载体中进行序列测定，并与国内外已公布的病毒核蛋白基因进行比对和分析。结果表明：此病毒的核酸序列与标准毒株RB－1、代表毒株WRAC的同源性分别为96．3％和93．6％；翻译出的氨基酸序列与标准毒株RB－1、代表毒株WRAC的同源性分别为96．1％和93．5％。系统进化树分析结果表明，此毒株与中国近期公布的毒株zyx有密切的亲缘关系。

Cloning and sequencing of nucleocapsid protein in infectious hematopoietic necrosis virus strain

The infectious hematopoietic necrosis virus （IHNV-DL） was amplified by RTG-2 cells, and the RNA in IHNV-DL was extracted by the TRIzol method. A gene of 786 bp was amplified from the nucleoprotein gene of IHNV-DL and cloned to the vector of pMD18-T in which the gene was sequenced and compared with the nucleoprotein gene of virus which was published. The results showed that the homology of nucleotide sequence was found to be 96.3% between the amplified products of the samples and IHNV reference strain RB-1, and 93.6% between the amplified products of samples and IHNV representative strain WRAC, with the homology of 96.1% and 93.5% between the induced amino acids sequence. The phylogenetic tree showed that the strain had a close relationship with the strain zyx published recently.