鸡痘病毒282E_4株2．2kbTK基因序列分析

Sequence Analysis of TK Gene in 2.2kb Fragment of FowIpox Virus 282E4 Genome

将鸡痘病毒２８２Ｅ４弱毒株基因组中的３．７ｋｂＨｉｎｄⅢ片段克隆到ＫＳ（—）质粒中，亚克隆后，获得含ＴＫ基因正反方向插入的２．２ｋｂＨｉｎｄⅢ－ＣｌａＩ片段的质粒ｐＫＦＡ和ｐＫＦＢ，进而构建出正反方向的系列嵌套缺失质粒。用Ｔ７、Ｔ３引物所做的核苷酸序列分析表明，２．２ｋｂＨｉｎｄⅢ－ＣｌａＩＴＫ基因序列长为２１５９ｂｐ，含有两个完整的读码框架（ＯＲＦ）Ｘ和ＴＫ，并确证了ＴＫ基因内存在单一酶切点ＮｃｏＩ。由该片段内的重复序列分析发现，在Ｘ和ＴＫ两个ＯＲＦ侧翼存在１５ｂｐ的正向重复序列。

The thymidine kinase(TK)gene of fowlpox virus (FPV)is located in a2.2 kb Hind Ⅲ-Cla Ⅰ fragment derived from the 3.7 kb Hind Ⅲ fragment of the FPV282E4 genome, It was subcloned into KS(-),and two plasmids, pKFA and pKFB,that contain 2.2 kb TK gene in right and reverse direction respectively,were construct-ed.Two series of nested deletion mutants were prepared with them,and sequence anal-ysis was done with T7and T3primers.It was shown that the fragment is 2 159 bp long,including two opening reading frames(ORF),X and TK,A Nco Ⅰ site is located in theTK gene.Further analysis found that the X and TK genes are flanked by 15 bp directrepeats.