Fig 6.
Covariance network for hepatitis B virus genotype B. (A) HBV genetic organization in its linear RNA phase. Cap, mRNA cap; pC, pre-C coding region that, together with the C sequences, encodes the HBeAg. C, core gene; TP, terminal protein domain of the polymerase gene; Spacer, spacer domain of the polymerase; RT, reverse transcriptase domain of the polymerase; RNaseH, RNase H domain of the polymerase; pS1, the pre-S1 domain of the largest of the three carboxy-coterminal surface proteins; pS2, the pre-S2 domain of surface proteins; SAg, the smallest surface protein (HBsAg); X, X gene; An, polyadenyl tail. The X and pre-C regions overlap in the circular DNA phase. (B) Network graph. The sizes of the nodes are proportional to the number of edges they contact, and the node numbers indicate the positions in the concatenated gene alignments (see Table S2 in the supplemental material). (C) Degree distribution plot.