A revised HindIII map and sequence analysis of a large 'left-hand' non-essential region of the rabbit poxvirus genome

Sequence analysis of a 21.5 kb region of the left-hand non-essential region of rabbit poxvirus (RPV) was performed to analyze the structure and gene organization of this region. Initial mapping and cloning studies revealed that the early published HindIII maps are incorrect in that the location of the terminal HindIII B and C fragments, as previously published, are reversed. The sequence of this region was compared to similar regions of several strains of vaccinia virus. The results indicate that this region of RPV has a high degree of homology with a similar region of vaccinia. Analysis of the translated open reading frames (ORFs) has facilitated the detection of several previously unreported ORFs related to human complement proteins. In addition, two defective copies of a homologue of the 77 kDa cowpox virus (CPV) host range gene which allows CPV to grow on Chinese hamster ovary cells have been detected, suggesting a gene duplication has occurred. However, one copy of this gene is segmented into three separate ORFs. Analysis has also identified a large number of indirect repeat elements. A possible role of these repeats in the generation of deletions and gene duplications is suggested.