Sequence of the avian adenovirus FAV 1 (CELO) DNA encoding the hexon-associated protein pVI and hexon

The genomic region of the avian adenovirus FAV1 (CELO) encoding the precursor to virion structural protein VI (pVI) and the major capsid protein hexon has been sequenced. The 223-unit sequence of the CELO pVI protein has two potential Ad endoproteinase cleavage sites and a conserved C-terminal sequence including the Cys residue supposedly involved in endoproteinase activation. The CELO hexon gene sequence predicts a 942-residue protein (106.7 kDa). Multiple sequence alignment with other six known hexon protein sequences (human, bovine, murine, and avian) reveals high overall homology. The identity is highest in the regions corresponding to the pedestals which form the base of the hexon, and lowest in the regions corresponding to the loops which are exposed on the outer surface of the virion.