Phylogenetic analysis of conserved genes within the ecdysteroid UDP-glucosyltransferase gene region of the slow-killing Adoxophyes orana granulovirus

A physical map of the genome of Adoxophyes orana granulovirus (AoGV) was co nstructed for the restriction enzymes BamHI, BgIII, EcoRI, PstI and SacI us ing restriction endonuclease analysis and DNA hybridization techniques. Thi s enabled the size of the AoGV genome to be estimated at 100.9 kbp. A plasm id library covering 99.9% of the AoGV genome was constructed using five res triction enzymes. The ecdysteroid UDP-glucosyltransferase gene (egt) was lo cated by hybridization with the egt gene of Cydia pomonella granulovirus. T he sequence of 6000 bp of the egt region is presented and compared to the e quivalent area in other GVs. Database searches showed that this region cont ained eight open reading frames (ORFs) similar to the baculovirus genes egt , granulin, pk-1, me53 and four ORFs of Xestia c-nigrum granulovirus (ORF 1 78, ORF 2, ORF 7 and ORF 8). The egt gene was shown to encode an active EGT using an EGT assay. Phylogenetic trees of the granulovirus genes egt, gran ulin, pk-1 and me53 were constructed using maximum parsimony and distance a nalyses. These analyses indicated that AoGV genes may be more closely relat ed to other tortricid-infecting GVs than to GVs that infect other lepidopte ran families.