粘虫核型多角体病毒凋亡抑制基因的定位、序列和启动子结构

Location, Sequence and Promoter Structure of Apoptosis Inhibiting Gene of Leucania seperate Nuclear Polyhedrosis Virus

以ＡｃＮＰＶ凋亡抑制基因ｐ３５为探针，与ＬｓＮＰＶＤＮＡ的限制性片段和ＬｓＮＰＶＤＮＡＥｃｏＲＶ片段杂交，发现ＥｃｏＲＶ５．５ｋｂ片段有强烈的杂交信号。将此片段亚克隆后，测定了１２４４ｂｐ序列，发现一个完整的ＯＲＦ，推导的３０２个氨基酸与ＡｃＮＰＶｐ３５蛋白有７０．４％的氨基酸同源性，证明所测ＯＲＦ为ＬｓＮＰＶ的ｐ３５基因。结构分析发现其５′端有早期基因启动子元件ＧＣ、ＡＣＧＴ和ＴＡＴＡｂｏｘ。有２２ｂｐ的顺向重复序列，包括由两个重叠的ＴＡＴＡｂｏｘ和上下游两个ＡＣＧＴｍｏｔｉｆ组成的两套启动子元件，这些结构特征与ＡｃＮＰＶ的凋亡抑制基因十分相似。

LsNPV DNA restriction fragments were hybridized with p 35 gene fragment of AcNPV. The 5.5 kb fragment of LsNPV was cleaved by single and double degestion and its physical map was constructed. After subcloning and sequencing, a intact ORF that is 906 bp in length, deduced amino acids are 302 in number was found. There are GC, ACGT motif and TATA box which are specific sequence of promoter of baculoviruses early gene. This ORF of LsNPV was compared with p 35 gene of AcNPV, and 80.4% nucleotide sequence homology and 70.4% amino acid sequence homology were found between two genes. Furthermore, in its promoter region there is 22 bp forward repeat, including 2 sets of promoter units, each is composed of 2 overlapping TATA box and 2 sets of ACGT motif in the upstream and the downstream of TATA box.