Capsid protein self-assembles to form rod-shaped virions about 20 nm in diameter with a central canal enclosing the viral genomic RNA. Isoform N-CP does not seem to be required for virion formation and systemic infection in host plant. Translationally initiated at a CTG codon 120 nucleotides upstream of the ATG initiation codon for the CP gene. Belongs to the virgaviridae capsid protein family.