致弱Ⅰ型MDV pp38基因同源物的克隆和序列分析

CLONING AND SEQUENCING OF pp38 GENE HOMOLOGUE OF MAREK′S DISEASE VIRUS ATTENUATED SEROTYPE I STRAIN

将致弱Ⅰ型马立克氏病病毒（ＭＤＶ）感染的细胞基因组ＤＮＡ的ＥｃｏＲⅠ酶切产物建于ｐＵＣ１８质粒载体文库中，以ｄｉｇｏｘｉｎｇｅｎｉｎ标记的含有强毒ＧＡ株ＭＤＶｐｐ３８基因克隆片段作为探针，进行原位杂交反应，初步筛选出阳性重组质粒，进一步用ＥｃｏＲⅠ酶切分析筛选到含ｐｐ３８基因同源物的重组ｐＵＣ１８质粒．序列分析表明该ｐｐ３８基因同源物与ｐｐ３８基因有极高的同源性。

Chicken embryonic fibroblasts (CEF) were infected with an attenuated Marek′s disease virus (MDV) serotype I strain and the MDV genomic DNA was extracted from the infected cells by pulsed field gel electrophoresis. The genomic DNA was digested with restriction endonuclease Eco RI and the recovered fragments were cloned into plasmid pUC18 as a genomic library. The library was screened for MDV pp38 gene homologue by in situ hybridization using digoxingenin labelled virulent MDV pp38 gene as the probe. Sequence analysis showed that MDV pp38 gene was highly conservative between the attenuated and virulent serotype I strains with only 1 base ( G→A ) difference.