IBDV超强毒株和弱毒株VP2基因同义密码子使用偏爱性研究

Study on the preference of synonymous codon usage of VP2 gene of very virulent IBDV and attenuated IBDV strains

应用RT-PCR方法扩增并克隆了分离自河南省的30株IBDV超强毒和9株弱毒株VP2基因cDNA序列,研究IBDV超强毒和弱毒株的VP2高变区基因不同位点同义密码子的使用情况。结果表明,超强毒株和弱毒株除特定位点的特征性氨基酸不同外,在同义密码子的使用上也有明显的偏爱性。这预示着同义密码子的使用与VP2基因表达及其表达产物的空间结构有关,进而可能影响到IBDV的毒力。

The VP2 gene cDNA of 30 very virulent IBDV isolates and 9 attenuated IBDV isolates that were cloned and amplified by RT-PCR in He＇nan province were compared. Synonymous codon usage in VP2 high variable region gene was studied. The results showed that many amino acids in synonymous codon usage had obvious preference besides the difference of the feature amino acids of very virulent IBDV and attenuated IBDV strains. This indicated that there was certain relation between the synonymous codon usage, VP2 gene expression and the space structure of its expression product,which may influence the virulence of IBDV.