Porcine circovirus type 3 (PCV3) is a highly contagious virus belonging to the family Circoviridae that causes the severe dermatitis and nephropathy syndrome. To date, PCV3 has a worldwide distribution and bring huge economic loss in swine industry. Replicase protein (Rep) and capsid protein (Cap) are two major proteins of PCV3. Considering that the large number of new PCV3 isolates were reported in the past few years and the research for the codon usage pattern of Rep and Cap genes was still a gap, phylogenetic and codon usage analysis of these two genes was performed. Phylogenetic analysis with all strains showed no clear clusters were displayed, but almost all strains of one genotype were separated into same clade. Relative synonymous codon usage (RSCU) analysis revealed that the codon usage bias existed and effective number of codon (ENC) analysis showed that the bias was slight low. ENC-GC3s plot indicated that mutational pressure and other factors both play a role in PCV3 codon usage and neutrality plot analysis showed that natural selection was the main force in uencing the codon usage pattern. In summary, the results provided the important basic data on codon usage pattern of Rep and Cap genes, and a better understanding of the evolution and potential origin of PCV3.

No abstract

Porcine circovirus type 3 (PCV3) is a highly contagious virus belonging to the family Circoviridae that causes the severe dermatitis and nephropathy syndrome. To date, PCV3 has a worldwide distribution and bring huge economic loss in swine industry. Replicase protein (Rep) and capsid protein (Cap) are two major proteins of PCV3. Considering that the large number of new PCV3 isolates were reported in the past few years and the research for the codon usage pattern of Rep and Cap genes was still a gap, phylogenetic and codon usage analysis of these two genes was performed. Phylogenetic analysis with all strains showed no clear clusters were displayed, but almost all strains of one genotype were separated into same clade. Relative synonymous codon usage (RSCU) analysis revealed that the codon usage bias existed and effective number of codon (ENC) analysis showed that the bias was slight low. ENC-GC3s plot indicated that mutational pressure and other factors both play a role in PCV3 codon usage and neutrality plot analysis showed that natural selection was the main force influencing the codon usage pattern. In summary, the results provided the important basic data on codon usage pattern of Rep and Cap genes, and a better understanding of the evolution and potential origin of PCV3.

No abstract