Fig 7. A model outlining the inhibitory effect of the p21.5 protein encoded by singly-spliced RNA on HBV replication.

(A) During regular HBV nucleocapsid assembly, viral core monomers initially form core homodimers and these then further assemble into the hexamer intermediates before the quick formation of the icosahedral nucleocapsid. (B) In the presence of p21.5, p21.5 proteins initially interact with each other and form homodimers. These p21.5 homodimers and the core homodimers then form mosaic viral particles that interfere with the formation of appropriate icosahedral nucleocapsid structure. The wild-type core protein is shown in gray; the p21.5 protein, which is encoded from singly-spliced RNA, is shown in red.