Self-assembles to form a helical, filamentous nucleocapsid mesuring 400 nm in length and 20 nm in width (Probable) (PubMed:32368353). Together with capsid protein 2, wraps arounds the DNA and maintains it in an A-form (Probable). Capsid proteins probably maintain the DNA in A-form by non-specific desolvation and specific coordination of the DNA phosphate groups by positively charged residues (Probable). This certainly protects the viral DNA under conditions such as the extreme desiccation of its host (Probable). Heterodimer composed of major capsid protein 1 and major capsid protein 2.