Self-assembles to form a helical capsid wrapping up the viral genomic DNA. Minor capsid protein involved in virus transmission by the vector S.subterranea. Associated with one extremity of viral particles. This protein is translated as a fusion protein by episodic readthrough of the termination codon at the end of the capsid protein. Readthrough of the terminator codon TAG occurs between the codons for Gln-188 and Gln-190 in about 10% of translation events, thereby producing the 75 kDa readthrough protein (PubMed:8757975). Belongs to the virgaviridae capsid protein family.