羊口疮病毒内脏和口唇感染株B2L和F1L基因的比较分析

Comparative Analysis of B2L and F1L Genes in Orf Virus Viscera and Lip Infected Strains

【目的】分析内脏和口唇感染羊传染性脓疱病病毒主要致病因子F1L和B2L基因和蛋白的差异,为进一步研究该病毒的致病机制提供参考。【方法】对内脏和口唇感染株F1L和B2L基因进行PCR扩增后克隆测序,运用生物信息学软件对其序列及编码蛋白的二级结构、磷酸化位点和跨膜结构域进行预测和分析。【结果】内脏株和口唇株的F1L基因长度均为1 564 bp,分别编码342和343个氨基酸;B2L基因长度均为1 370 bp,均编码378个氨基酸。内脏和口唇感染株B2L基因核苷酸序列同源性为97.80%,氨基酸序列同源性为98.15%;两者的F1L基因核苷酸序列同源性为95.49%,氨基酸序列同源性为87.20%。氨基酸组成显示:内脏和口唇感染株B2L蛋白缬氨酸含量最高;口唇株F1L蛋白亮氨酸含量最高,内脏株F1L蛋白精氨酸含量最高。【结论】羊口疮病毒内脏和口唇感染株的B2L基因保守性良好,而F1L基因差异明显,本结果可为进一步研究羊口疮病毒致病机制提供参考。

[Purpose]To analyze the differences in the genes and proteins of F1L and B2L,the main virulence factors of contagious ecthyma virus in visceral and lip infections,providing a reference for further research on the virulence mechanism of this virus.[Methods]The F1L and B2L genes of the viscera and lip infected strains were cloned and sequenced after PCR amplification,and their sequences and the secondary structures,phosphorylation sites,and transmembrane structural domains of the encoded proteins were predicted and analyzed by using bioinformatics software.[Results]The F1L gene of both viscera and lip strains was 1564 bp in length,encoding 342 and 343 amino acids,respectively;the B2L gene was 1370 bp in length,both encoding 378 amino acids. The nucleotide sequence homology of the B2L genes of the lip and viscera infected strains was 97.80%, and the amino acid sequence homology was 98.15%. The nucleotide sequence homology of the F1L genes of the lip and viscera infected strains was 95.49%, and the amino acid sequence homology was 87.20%. The amino acid compositions showed that the B2L protein had the highest content of valine in both viscera and lip strains;the F1L protein had the highest content of isoleuine in lip strain, and had the highest content of arginine in viscera strain. [Conclusion]The B2L gene is well conserved in the viscera and lip infected strains of contagious ecthyma virus, while the F1L gene is obviously different, which may provide a reference for further research on the pathogenic mechan-ism of contagious ecthyma virus.