Characterization of the avian adenovirus penton base.

A portion of the fowl adenovirus 10 (FAV-10) penton base gene was located within a Sau3A genomic DNA fragment by the combination of a plasmid expression library and colony immunoassays with rabbit anti-FAV-10-sera. The coding portion of the sequence contained in the expression vector was mapped to a 11.6-kb Bg/II fragment and more precisely mapped to the right-hand end of the 11.6-kb fragment at map units 37.7 to 41.3. Nucleotide sequence analysis of the region revealed an open reading frame of 1575 bp with translation of the sequence producing a polypeptide of 525 amino acids in length. The polypeptide predicted from the open reading frame would have a molecular weight of 57.4 kDa. Analysis of the amino acid sequence revealed an overall homology of 41.8% with the human adenovirus 2 (HAV-2) penton base. However, a region near the center of the polypeptide (amino acids 219 to 311) showed a significantly greater level of homology to the HAV-2 penton base (71%). Time course experiments using mRNA confirmed that this gene is expressed at late times postinfection. Upon probing genomic DNA from other FAV serotypes the penton base coding region hybridized to all six different serotypes tested, indicating a relatively conserved DNA sequence among a variety of FAVs.