Strongly bound to viral DNA and responsible for wrapping and condensing the viral DNA. Probably promotes viral genome import into the nucleus and is still associated with the viral DNA when the latter enters into the host nucleus (By similarity). Interacts with the core-capsid bridging protein; this interaction bridges the virus core to the capsid. Located inside the capsid in association with the viral DNA (core). Present in about 1070 copies per virion (By similarity). Expressed in the late phase of the viral replicative cycle. Cleaved near the N-terminus by the viral protease during virion maturation to form the mature protein. 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 (By similarity). Belongs to the adenoviridae histone-like nucleoprotein family.