传染性法氏囊病病毒Gt株基因组A节段的克隆和序列分析

Cloning and sequencing of infectious bursal disease virus gt genomic segment A

利用SPF鸡胚对鸡传染性法氏囊病超强毒vvIBDV_Gx株进行培育 ,通过鸡胚成纤维细胞对病毒进行传代致弱 ,使其成为弱毒株IBDV_Gt。从细胞适应毒中提取病毒dsRNA ,通过反转录 ,使用Long_accuratePCR(LA_PCR)用一对引物一步直接扩增IBDV_Gt基因组A节段全长cDNA的方法 ,得到一约 3 30kb的片段。测序结果证明已获得 32 5 5bp的A节段全长 ,对vvIBDV_Gx株和IBDV_Gt株的全部核苷酸及推导的氨基酸序列进行分析 ,结果表明IBDV_Gt株与国内外数株IBDV弱毒株的同源性在

Very virulent infectious bursal disease virus (vvIBDV) Gx strain was cultured in SPF embryo and attenuated by passage on chicken embryo fibroblast(CEF).Thus ,the IBDV-Gt strain was gained.The double strand genomic RNA was extracted from CEF adapted virus strain. About 3.3 kb full_length segment A was synthesized by reverse transcription, followed by the Long_accurate polymerase chain reaction (LA_PCR) in one step amplification of single strand cDNA, The result of sequencing verified that the 3 255 bp full_length DNA of segment A was gained.The segment A sequence of nucleotide and the deduced amino acid sequence was analyzed,the results indicated that there is more than 99 % homology between the IBDV_Gt strain and other attenuated strains.