In the present study, we examined the codon usage bias between pseudorabies virus （PRV） US1 gene and the USl-like genes of 20 reference alphaherpesviruses. Comparative analysis showed noticeable disparities of the s...In the present study, we examined the codon usage bias between pseudorabies virus （PRV） US1 gene and the USl-like genes of 20 reference alphaherpesviruses. Comparative analysis showed noticeable disparities of the synonymous codon usage bias in the 21 alphaherpesviruses, indicated by codon adaptation index, effective number of codons （ENc） and GC3s value. The codon usage pattern of PRV US1 gene was phylogenetically conserved and similar to that of the USl-like genes of the genus Varicellovirus of alphaherpesvirus, with a strong bias towards the codons with C and G at the third codon position. Cluster analysis of codon usage pattern of PRV US1 gene with its reference alphaherpesviruses demonstrated that the codon usage bias of USl-like genes of 21 alphaherpesviruses had a very close relation with their gene functions. ENc-plot revealed that the genetic heterogeneity in PRV US1 gene and the 20 reference alphaherpesviruses was constrained by G＋C content, as well as the gene length. In addition, comparison of codon preferences in the US1 gene of PRV with those ofE. coli, yeast and human revealed that there were 50 codons showing distinct usage differences between PRV and yeast, 49 between PRV and human, but 48 between PRV and E. coil Although there were slightly fewer differences in codon usages between E.coli and PRV, the difference is unlikely to be statistically significant, and experimental studies are necessary to establish the most suitable expression system for PRV US1. In conclusion, these results may improve our understanding of the evolution, pathogenesis and functional studies of PRV, as well as contributing to the area of herpesvirus research or even studies with other viruses.展开更多
基金supported by grants from the Scientific Research Foundation for the Ph.D.,Guangzhou Medical University(2011C20)National Natural Science Foundation of China(31200120)+1 种基金Medical Scientific Research Foundation of Guangdong Province,China(B2012165)the Guangzhou city-level key disciplines and specialties of Immunology(B127007)
文摘In the present study, we examined the codon usage bias between pseudorabies virus （PRV） US1 gene and the USl-like genes of 20 reference alphaherpesviruses. Comparative analysis showed noticeable disparities of the synonymous codon usage bias in the 21 alphaherpesviruses, indicated by codon adaptation index, effective number of codons （ENc） and GC3s value. The codon usage pattern of PRV US1 gene was phylogenetically conserved and similar to that of the USl-like genes of the genus Varicellovirus of alphaherpesvirus, with a strong bias towards the codons with C and G at the third codon position. Cluster analysis of codon usage pattern of PRV US1 gene with its reference alphaherpesviruses demonstrated that the codon usage bias of USl-like genes of 21 alphaherpesviruses had a very close relation with their gene functions. ENc-plot revealed that the genetic heterogeneity in PRV US1 gene and the 20 reference alphaherpesviruses was constrained by G＋C content, as well as the gene length. In addition, comparison of codon preferences in the US1 gene of PRV with those ofE. coli, yeast and human revealed that there were 50 codons showing distinct usage differences between PRV and yeast, 49 between PRV and human, but 48 between PRV and E. coil Although there were slightly fewer differences in codon usages between E.coli and PRV, the difference is unlikely to be statistically significant, and experimental studies are necessary to establish the most suitable expression system for PRV US1. In conclusion, these results may improve our understanding of the evolution, pathogenesis and functional studies of PRV, as well as contributing to the area of herpesvirus research or even studies with other viruses.
