传染性囊病病毒CJ801 VP2基因cDNA的序列分析  

SEQUENCE ANALYSIS OF cDNA GENE CODING FOR VP2 OF CJ801 STRAIN OF INFECTIOUS BURSAL DISEASE VIRUS

作　　者：曹永长[1,2,3] 毕英佐[1,2,3] 梁志清[1,2,3] 周蛟[1,2,3] 林文量[1,2,3] 

机构地区：[1]华南农业大学动物科学系 [2]香港大学动物学系 [3]北京农林科学院畜牧兽医研究所

出　　处：《华南农业大学学报》1997年第A00期65-72,共8页Journal of South China Agricultural University

基　　金：国家攀登计划项目;香港政府工业署工业支援计划资助

摘　　要：用ＲＴ－ＰＣＲ从传染性囊病病毒ＣＪ８０１的第１４代囊毒中扩增编码ＶＰ２蛋白的ｃＤＮＡ基因片断，长度为１５００ｂｐ，并对该片断进行了ＤＮＡ序列分析。结果表明，ＣＪ８０１与ＩＢＤＶ标准Ⅰ型毒株５２／７０、ＳＴＣ和Ｃｕｌ的同源性最高，分别为９７４％、９７６％和９６９％，与变异株Ａ、Ｅ、ＧＬＳ的同源性稍低，分别为９６５％、９６３％和９６７％。而与Ⅱ型毒株的同源性只有８１％左右。从遗传进化树上看，ＣＪ８０１处于标准Ⅰ型毒株和变异株之间。根据ｃＤＮＡ序列推导出蛋白质序列，比较蛋白质序列发现，ＣＪ８０１与Ⅰ型ＩＢＤＶ毒株的同源性均在９６％以上，其中与５２／７０的同源性最高，为９８２％。ＣＪ８０１ＶＰ２高可变区的七肽区（Ｓ－Ｗ－Ｓ－Ａ－Ｓ－Ｇ－Ｓ）未发生变化。以上结果说明ＣＪ８０１为ＩＢＤＶⅠ型强毒株。另外，ＣＪ８０１和所有ＩＢＤＶ强毒株在ＶＰ２的２５３、２７９和２８４位上的氨基酸均相同，分别为Ｑ、Ｄ和Ａ；而ＣＪ８０１的细胞适应株ＣＪ８０１ＢＫＦ和所有弱毒株一样，其相应位置的氨基酸分别为Ｈ、Ｎ和Ｔ。这３个氨基酸可能和ＩＢＤＶ的毒力有关。?A cDNA fragment with a length of 1500bp coding for VP2 of infectious bursal disease virus (IBDV) has been amplified by reverse transcription-polymerase chain reaction(RT-PCR)from CJ 801 strain isolated in China. DNA sequence analysis showed that the similarities of nucleotide sequence of CJ801 strain with classical type I strains 52/70, STC and Cul were 97.4%, 97.6% and 96.9% respectively, those with variant strains A, E and GLS were a little smaller, 96.5%, 96.3% and 96.9%,respectively, and those with type Ⅱ strains were about 81%. Cluster analysis of nucleotide sequences indicated that CJ801 strain is more closely related to classical virulent strains and classical tissue culture-adapted strains than to variant strains, very virulent strains and type Ⅱ strains. Comparison of deduced amino acid sequences showed that the homogenneities of CJ 801 strain with all classical type I strains were over 96%.The most closely related strain to CJ801 strain is 52/70 strain, in which the divergence of amino acid sequences was only 1.8%. A serine-rich heptapeptide(S-W-S-A-S-G-S),which is a signature of virulent IBDV strains, is also present in CJ801, indicating that CJ801 is a classical virulent IBDV strain.At positions 253,279 and 284,the amino acid residues of CJ801 strain are Q, D and A respectively, conserved in that of virulent strains . However, in the attenuated strain of CJ801 (CJ801 BKF),the residues at these positions were substituted by H,N and T respectively.There substitutions were commonly found in cell culture adapted IBDV strains. It is suggested that these amino acid residues, 253 Q,279 D and 284 A can be regarded as signature of virulent strains of IBDV in addition to the serine rich heptapeptide.

关 键 词：鸡病 传染性囊病 病毒 基因克隆 序列分析 

分 类 号：S858.315.3[农业科学—临床兽医学] S852.4[农业科学—兽医学]