Associates loosely with the viral DNA to form an outer shell around the nucleoprotein-DNA complex and links it with the capsid by binding the endosome lysis protein. Dissociates from the viral genome during entry. Might be involved in nuclear capsid assembly of the viral particles through its association with NPM1/nucleophosmin. Monomer. Homodimer. Exists in equilibrium between monomers and dimers in solution. Interacts with the histone-like nucleoprotein; this interactions bridge the virus core to the capsid. Interacts with core protein X; this interactions bridge the virus core to the capsid. Interacts with the endosome lysis protein VI; this interactions bridge the virus core to the capsid. Interacts with the peripentonal hexons. Interacts with host NPM1; this interaction might play a role in virus assembly. Located inside the capsid (core). Present in 157 copies per virion. Localizes in the nucleoli during infection, then translocates from the nucleoli to the nucleoplasm as the infection progresses and is finally incorporated into the viral particles. Expressed in the late phase of the viral replicative cycle. All late proteins expressed from the major late promoter are produced by alternative splicing and alternative polyadenylation of the same gene giving rise to non-overlapping ORFs. A leader sequence is present in the N-terminus of all these mRNAs and is recognized by the viral shutoff protein to provide expression although conventional translation via ribosome scanning from the cap has been shut off in the host cell. This protein is only encoded by mastadenoviruses, and may therefore play a role in mammals tropism. Belongs to the adenoviridae core-capsid bridging protein family.