不同传染性法氏囊病病毒分离株变异的研究

目的 了解不同源IBDV和不同血清亚型IBDV病毒株的变异情况。方法 用琼脂糖凝胶电泳。SDS-PAGE和序列分析等分离生物学方法分析病毒RNA、结构蛋白的变异情况。结果 (1)三种不同源IBDV均由双节段RNA组成,大小基因片段的电泳迁移率在各病毒株间无差异;(2)SDS-PAGE分析表明各IBDV的结构蛋白带谱相同,但各蛋白带的百分含量有差异;(3)序列分析表明JS3、JS4与标准对照病毒株S1 IBDV VP2基因片段的核酸的同源性均为97％,JS_3与JS_4的同源性为99％。推导编码蛋白氨基酸序列,JS_3与S_1的同源性为97％,JS4与s1的同源性为96％,JS3与JS4的同源性为98％。结论 我国流行的IBDV病毒株与标准病毒株相比不仅在免疫学反应上有差异,而且在病毒核酸序列上有变异,这种变异是造成疫苗免疫失败或免疫逃避的分子基础。

Study on the molecular biology of infectious bursal disease virus (IBDV)

To investigate the variation status of different source of IBDV and the different subtype of IBDV. MethodsVariation status on virul RNA and structural protein were analyzed with agarose electrophorisis, SDS-PAGE and sequence analysis. Results (1)IBDV of three different source consists of two fragments, The rates of RNA migration of large and small fragments in agarose gels were of no diffreence for different strains; (2)Analysis fo IBDV by SDS-PAGE showed the same spectrum of structural protein, but the relative percentage contents were different; (3) sequence analysis showed 97% homology between JS3 and standard strain S1,97% homology between JS4 and SI, 99% homology between JS3 and JS4. The homology of amino acid sequences deduced with PROSIS computer system was 97% between JS3 ans SI,and 96%between JS4 and SI, and 98% between JS3 and JS4. Conclusion The IBDV prevailing in our country exists difference in immunology and nucleotide sequence mutations exists in comparison with standard strain. This mutation may be molecular basis of failure of escape of immunization