Fig. 11.

Assembly of a capsid around a polyelectrolyte cargo (e.g. a nucleic acid). Red is the nucleic acid cargo and blue is the coat protein. At low ionic strength (stronger coat–cargo interactions) and weak cargo–cargo interactions, an en masse mechanism is favored (A). The nucleation and growth mechanism is favored when coat–cargo interactions are weaker (higher ionic strength) and stronger coat–coat interactions. Figure adapted from ref. 156 with permission from Elsevier, copyright 2014.