File:Viruses-13-01913-g002-550.jpg

English: Herpesvirus capsid assembly pathway. (a) Capsid assembly is thought to be nucleated by the portal complex that interacts with the MCP, triplexes, or scaffold. The MCP and triplexes assemble around the scaffold into a spherical procapsid. (b) The terminase complex binds to the portal and the protease cleaves the scaffold. The capsid is angularized, the scaffold is extruded, and the DNA genome is packaged into the capsid. (c) The DNA is then cleaved and the terminase is released, resulting in the formation of a mature C-capsid. B-capsids (d) and A-capsids (e) are thought to be the by-products of assembly. B-capsids form whenever the scaffold fails to be released from the capsid whereas A-capsids form if the scaffold is released but the DNA does not get packaged. The top inset illustrates the open capsid structures observed in some of the capsid assembly experiments described in the text. For clarity, the SCP and auxiliary proteins are not shown. The figure was created with BioRender.com, accessed on 10 July–19 September 2021.