We have determined the complete DNA sequence of the Leporipoxvirus Shope fi
broma virus (SFV). The SFV genome spans 159.8 kb and encodes 165 putative g
enes of which 13 are duplicated in the 12.4-kb terminal inverted repeats. A
lthough most SFV genes have homologs encoded by other Chordopoxvirinae, the
SFV genome lacks a key gene required for the production of extracellular e
nveloped virus. SFV also encodes only the smaller ribonucleotide reductase
subunit and has a limited nucleotide biosynthetic capacity. SFV preserves t
he Chordopoxvirinae gene order from S012L near the left end of the chromoso
me through to S142R (homologs of vaccinia F2L and B1R, respectively). The u
nique right end of SFV appears to be genetically unstable because when the
sequence is compared with that of myxoma virus, five myxoma homologs have b
een deleted (C. Cameron, S. Hota-Mitchell, L. Chen, J. Barrett, J.-X. Cao,
C. Macaulay, D. Willer, D. Evans, and G. McFadden, 1999, Virology 264, 298-
318). Most other differences between these two Leporipoxviruses are located
in the telomeres. Leporipoxviruses encode several genes not found in other
poxviruses including four small hydrophobic proteins of unknown function (
S023R, S119L, S125R, and S132L), an alpha 2,3-sialyltransferase (S143R), a
protein belonging to the Ig-like protein superfamily (S141R), and a protein
resembling the DNA-binding domain of proteins belonging to the HIN-200 pro
tein family S013L). SFV also encodes a type II DNA photolyase (S127L). Mela
noplus sanguinipes entomopoxvirus encodes a similar protein, but SN is the
first mammalian virus potentially capable of photoreactivating ultraviolet
DNA damage. (C) 1999 Academic Press.