Complete genomic sequence of the Amsacta moorei entomopoxvirus: Analysis and comparison with other poxviruses

The genome of the genus B entomopoxvirus from Amsacta moorei (AmEPV) was se quenced and found to contain 232,392 bases with 279 unique open reading fra mes (ORFs) of greater than 60 amino acids. The central core of the viral ch romosome is flanked by 9.4-kb inverted terminal repeats (ITRs), each of whi ch contains 13 ORFs, raising the total number of ORFs within the viral chro mosome to 292. ORFs with no known homology to other poxvirus genes were sho wn to constitute 33.6% of the Viral genome. Approximately 28.6% of the AmEP V genome encodes homologs of the mammalian poxvirus colinear core genes, wh ich are found dispersed throughout the AmEPV chromosome. There is also no s ignificant gene order conservation between AmEPV and the orthopteran genus B poxvirus of Melanoplus sanguinipes (MsEPV). Novel AmEPV genes include tho se encoding a putative ABC transporter and a Kunitz-motif protease inhibito r. The most unusual feature of the AmEPV genome relates to the viral encode d poly(A) polymerase. In all other poxviruses this heterodimeric enzyme con sists of a single large and a single small subunit. However, AmEPV appears to encode one large and two distinct small poly(A) polymerase subunits. AmE PV is one of the few entomopoxviruses which can be grown and manipulated in cell culture. The complete genomic sequence of AmEPV paves the way for an understanding and comparison of the molecular properties and pathogenesis b etween the entomopoxviruses of insects and the more intensively studied ver tebrate poxviruses. (C) 2000 Academic Press.