The Complete Genome Sequence of Shope (Rabbit) Fibroma Virus

Abstract

We have determined the complete DNA sequence of the Leporipoxvirus Shope fibroma virus (SFV). The SFV genome spans 159.8 kb and encodes 165 putative genes of which 13 are duplicated in the 12.4-kb terminal inverted repeats. Although most SFV genes have homologs encoded by other Chordopoxvirinae, the SFV genome lacks a key gene required for the production of extracellular enveloped virus. SFV also encodes only the smaller ribonucleotide reductase subunit and has a limited nucleotide biosynthetic capacity. SFV preserves the Chordopoxvirinae gene order from S012L near the left end of the chromosome through to S142R (homologs of vaccinia F2L and B1R, respectively). The unique right end of SFV appears to be genetically unstable because when the sequence is compared with that of myxoma virus, five myxoma homologs have been 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 protein family S013L). SFV also encodes a type II DNA photolyase (S127L). Melanoplus sanguinipes entomopoxvirus encodes a similar protein, but SFV is the first mammalian virus potentially capable of photoreactivating ultraviolet DNA damage.

Host-specificity of myxoma virus: Pathogenesis of South American and North American strains of myxoma virus in two North American lagomorph species

“…A third leporipoxvirus, Shope fibroma virus, is present in Sylvilagus floridanus (eastern cottontail) in North America. Although genetically and antigenically closely related to myxoma virus, this virus does not cause disseminated disease in immunocompetent European rabbits (Cameron et al, 1999;Fenner, 1965;Woodroofe and Fenner, 1965;Willer et al, 1999) but induces a cutaneous fibroma at the inoculation site. Myxoma virus has a double strand DNA genome of 161 kb.…”

“…Like other poxviruses, the central part of the genome contains genes required for virus replication and assembly that tend to be conserved across the poxvirus family. However, the outer parts of the genome encode genes required for host-specificity and immune modulation that tend to be unique to the leporipoxviruses (Cameron et al, 1999;Willer et al, 1999;Stanford et al, 2007). These genes are presumed to have closely evolved with the natural host in order to allow the virus to replicate and maintain high titres in the epidermis at the inoculation site for sufficient time to be transmitted by biting arthropods.…”

M135R Is a Novel Cell Surface Virulence Factor of Myxoma Virus

“…Here we have characterized the M135R version identified in MV as a putative ortholog of VV B18R. M135R is half the size of the ortholog encoded by other poxvirus members (Table 1), and the other sequenced member of the leporipoxviruses, Shope fibroma virus, has a fragmented version of even this truncated open reading frame (31). The observations that members of the para-and molluscipoxviruses do not encode an obvious functional inhibitor of type I IFNs and that the leporipoxviruses encode truncated, non-IFN-related ORFs suggest that each has evolved to block type I IFN in a manner that has diverged from that observed for other poxvirus members.…”

Development of a DNA microarray-based multiplex assay of avian influenza virus subtypes H5, H7, H9, N1, and N2

“…PCR-amplified viral cDNAs were subsequently cloned using a Topo TA cloning kit (Invitrogen). Recombinant plasmids were purified from lacZ mutant bacteria and sequenced as described previously (Willer et al, 1999). The recombinant plasmids were used for PCR.…”