Submitted to: Journal of Invertebrate Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/24/2006
Publication Date: 1/16/2007
Citation: Green, T.B., White, S., Rao, S., Mertens, P., Adler, P.H., Becnel, J.J. 2007. Biological and molecular studies of a cypovirus from the black fly simulium ubiquitum (diptera: simuliidae). Journal of Invertebrate Pathology 95 (2007):26-32. Interpretive Summary: A naturally occurring virus that infects black flies has been characterized by ARS scientists at the Center for Medical, Agricultural and Veterinary Entomology, Gainesville Florida. We have conducted biological and molecular study and determined that this RNA virus has a 10 segmented genome and sequence analysis of the occlusion body protein has determined this species (SuCPV) is a new member of the Cypoviruses (SuCPV-20). This new virus fromblack flies expands the genetic diversity base required to investigate and understand basic mechanisms involved in infectivity and host range that will enhance capabilities to use these viruses for black fly control.
Technical Abstract: A cypovirus from the blacklfy Simulium ubiquitum (SuCPV) was isolated and examined using biological and molecular techniques. SuCPV produces small (0.5 to 1.0µm), polyhedral shaped inclusion bodies (polyhedra), in which the virus particles become multiply embedded. SuCPV is the third cypovirus isolated from Diptera, but the first from Simuliidae that has been characterized using molecular analyses. SuCPV has a genome composed of 10 segments of dsRNA, with an electrophoretic migration pattern that is different from those of recent UsCPV-17 and CrCPV-17 isolates from the mosquitoes Uranotaenia sapphirina and Culex restuans, respectively. The SuCPV electropherotype appears to show significant differences from those of the previously characterized lepidopteran cypoviruses. Sequence analysis of SuCPV segment 10 shows that it is unrelated to either of the two CPV isolates from Diptera or to the CPV species for which Seg-10 has been previously characterized from Lepidoptera. A comparison of the terminal regions of SuCPV genome segments to those of CPV- 1, 2, 4, 5 14, 15, 16, 17 18 and 19 also revealed only low levels of conservation. We therefore, propose that SuCPV is classified within a new Cypovirus species, which we have tentatively identified as Cypovirus-20. We have therefore referred to this virus isolate as Simulium ubiquitum CPV-20 (SuCPV-20).