Complete sequence and organization of Periplaneta fuliginosa densovirus genome.

The replicative form (RF) of the Periplaneta fuliginosa densovirus (PfDNV) genome was cloned and its complete nucleotide sequence was determined. The PfDNV genome is 5454 nucleotides (nt) in length with distal 201-nt long inverted terminal repeats (ITRs). The first 122 nt at the 5'-end and the terminal 122 nt at the 3'-end of both strands are palindromes with identical sequences, of which each can fold into a typical U-shaped hairpin structure. The coding regions of PfDNV genome are evenly distributed in the 5'-halves of both strands. PfDNV genome contains seven major open reading frames (ORFs), four of which on the plus DNA strand may encode non-structural (NS) proteins, while the others on the minus DNA strand may encode structural proteins. Two potential functional promoters (P3 and P97) were found within the ITRs on both strands. The ORF2 polypeptide contains a highly conserved NTP-binding domain of NS proteins of parvoviruses. The ORF5 polypeptide has significant homology to the conserved PGY region of coat proteins of parvoviruses. The ORF6 polypeptide has distinct homology to the structural polypeptides of insect parvoviruses. The organization of PfDNV genome was compared to those of other parvoviruses.