Relaxed template specificity in fowl adenovirus 1 DNA replication initiation.
The fowl adenovirus 1 (FAdV-1) isolates PHELPS and OTE are highly similar, but have striking differences in the repeat region of the inverted terminal repeat (ITR). Whilst the repeat region in OTE conforms to the conventional human adenovirus repeat region (5'-CATCATC), that of PHELPS contains guanidine residues at positions 1, 4 and 7 (5'-GATGATG). This implies that the FAdV-1 isolates PHELPS and OTE have either distinct template specificity at replication initiation or, alternatively, a relaxed specificity for replication initiation. In this study, the distinct sequence variation at the origin of DNA replication in the ITRs of the FAdV-1 PHELPS and OTE isolates was confirmed. Sequence analyses of the pTP and Pol genes of both PHELPS and OTE did not reveal differences that could explain the distinct template specificity. Replication assays demonstrated that linear DNA fragments flanked by either 5'-CATCATC or 5'-GATGATG termini replicated in cells upon infection with FAdV-1 OTE and FAdV-1 PHELPS. This was evident from the appearance of DpnI-resistant fragments in a minireplicon assay. From these data, it is concluded that FAdV-1 has relaxed, rather than changed, its template specificity at replication initiation.
Department of Molecular Cell Biology, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands.
Hendrik J
HJ
Rademaker
Department of Molecular Cell Biology, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands.
Frits J
FJ
Fallaux
Department of Molecular Cell Biology, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands.
Diana J M
DJM
Van den Wollenberg
Department of Physiological Chemistry and Center for Biomedical Genetics, University Medical Center, Universiteitsweg 100, 3508 AB Utrecht, The Netherlands.
Rob N
RN
De Jong
Department of Physiological Chemistry and Center for Biomedical Genetics, University Medical Center, Universiteitsweg 100, 3508 AB Utrecht, The Netherlands.
Peter C
PC
Van der Vliet
Department of Molecular Cell Biology, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands.
Rob C
RC
Hoeben
D000595:Amino Acid Sequence; D001483:Base Sequence; D004279:DNA, Viral / Q000096:biosynthesis; D025681:Fowl adenovirus A / Q000235:genetics*; D015684:Gene Products, pol / Q000235:genetics; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics; D011498:Protein Precursors / Q000235:genetics; D016415:Sequence Alignment; D013045:Species Specificity; D013698:Templates, Genetic; D020079:Terminal Repeat Sequences / Q000235:genetics*; D014764:Viral Proteins / Q000235:genetics
D004279:DNA, Viral; D015684:Gene Products, pol; D010750:Phosphoproteins; D011498:Protein Precursors; D014764:Viral Proteins; C085476:pTP protein, adenovirus