Schematic representations of (A) HCRSV genome and (B) partial HCRSV CP sequence showing mutation sites and deletion.

Rectangles in (A) represent open reading frames. Underlined amino acids in (B) indicate the non-expressed portion as the CP start codon ATG was replaced with GTG in mutant p2590 (A to G) and the boxed proline (CCG) was substituted with alanine (GCG) to remove the kink of CP in mutant p2776 (C to G). The circled methionine residues are the translation initiation sites of CP in wt HCRSV (p223) and mutant p2590 (A to G). Symbol slash (/) represents the cleavage site when swollen HCRSV virions were digested with trypsin.