Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 13, 1995
Publication Date: N/A
Bluetongue virus (BLU), an orbivirus, is an important agent to the sheep and cattle industry. Our goal is to identify goal is to identify markers of virulence for BLU-17. We have identified two characteristics which are associated with virulence - an antigenic change in the outer capsid protein, VP2, and a genetic change in segment 3 which encodes an inner core protein, VP3. The antigenic change in VP2 involves at least two neutralizing epitopes. The genetic change in segment 3 is characterized by a difference in migration on polyacrylamide gels. VP2 is encoded by segment 2; therefore, these two putative virulence markers are encoded by two genes which reside on different genome segments. We have sequenced segments 2 and 3 of one virulent and one avirulent BLU-17 isolate. Sequence analysis of segment 2 revealed 94% nucleotide identity and 96% deduced amino acid identity, and analysis of segment 3 revealed 95% nucleotide identity and 98% deduced amino acid identity. In summary, genome segments 2 and 3 are associated with virulence in BLU-17, and we hypothesize that one or both of these genes is important for bluetongue virulence. Pathogenesis studies are ongoing to test this hypothesis.