FIG 9.

Regulation of specific versus nonspecific RNA packaging of HBV capsids by the degree of CTD phosphorylation and dephosphorylation. The HBc CTD state of phosphorylation is proposed to be regulated dynamically by the host protein kinase(s) and phosphatase(s). The letter P on the capsids denotes phosphorylation. The specific viral pgRNA is depicted as a thick and long wavy line inside the capsid (diamond), and the nonspecific RNAs are depicted as thin and short wavy lines. The dashed arrow indicates that under natural replication conditions in human cells, HBc is unlikely to be in a nonphosphorylated state upon expression and thus that few capsids with nonspecific RNA packaging would form, in contrast to capsid assembly in E. coli. See the text for details. For clarity, RT packaging is not shown.