Figure 4.

Herpesviridae viruses infecting mammalian hosts carry preferentially C-looped motifs. (A) Principal component analysis (PCA) performed on loop composition information (variables: PQS^A, PQS^T, PQS^C, PQS^G) for 93 herpesviruses, without using host group information. Ellipses indicate barycenters (weighted center of mass) for each host group. (B) Proportion of single C (orange, top panel) or G (blue, bottom panel) loops by host group. Bars indicate the upper and lower bounds of the 95% confidence intervals. Chi-square independence tests were used to evaluate the significance of the association between loop proportions and host group. Red arrows indicate groups with pairwise nominal independence adjusted P-values <0.05. (C) Relationship between PQS^A (PQS^T or PQS^C) motif and PQS^G motif contents. Pearson correlation coefficients are reported on each graph. Blue lines show linear regressions (P_reg, linear regression significance).