鸭瘟病毒AV1221株TK基因的克隆与序列分析

Cloning and Sequence Analysis of TK Gene of Duck Plague Virus AV1221 Strain

根据发表的鸭瘟病毒弱毒TK（thymidine kinase）基因序列设计、合成一对引物。采用该引物利用PCR克隆出大小为1275bp鸭瘟病毒强毒AV1221株TK基因片段。将扩增的DNA片段纯化后连接到pMD-18T载体上,筛选获得阳性重组质粒pMD-TK。对重组质粒中的插入片段测序,利用DNAMAN软件进行序列分析和同源性比较。结果表明鸭瘟病毒AV1221株TK基因ORF全长为1077bp,编码358个氨基酸。与参考序列比较,核苷酸同源性为99.4%～99.9%,TK蛋白氨基酸的同源性为98.6%～99.7%。

A pair of primers were designed and synthesized according to the published sequences data of the TK gene of a vaccine duck plague virus （DPV） strain. Using these primers, an expected 1275 - bp DNA fragment comprising the complete TK gene open reading frame （ORF） of DPV AV1221 strain（named DPV - AV1221 ） was amplified by polymerase chain reaction （PCR）. The DNA product was purified and linked into pMD18 -T vector, and the positive recombinant plasmids were designated pMD -TK. After sequencing, the TK gene ORF was analyzed and compared with those in other DPV strains using DNAMAN software. It revealed that the TK ORF of DPV -AV1221 was 1077 -bp in size and encoded 358 amino acids. Compared with other three DPV strains, the TK ORF of DPV - AV1221 has the homology from 99.4% to 99.9% in nucleic acids level, and from 98.6% to 99. 7% in amino acids level.