Genetic diversity of viruses of Chenuda virus species (Orbivirus, Reoviridae) circulating in Central Asia.

Chenuda virus (CNUV) (Orbivirus, Reoviridae) is the only known orbivirus associated with argas (Argasidae) ticks. Scientific study of this group is necessary for understanding of Orbivirus genus evolution patterns. We conducted a comparative analysis of full genomes of five different viruses of Chenuda virus species, including Baku virus strains (BAKV) circulating in a rather limited area in the Central Asia and Transcaucasia. It was shown that VP4(OC1) and VP6(Hel) proteins variability greatly exceeds the variability of other proteins. The divergence between CNUV and BAKV in this proteins is about 50%. Even in closely related strains isolated from the same geographical region, the conservative genes of which are 90-95% identical, the VP4(OC1) and VP6(Hel) divergence reaches values that would usually be indicative of different serotypes (74.1-82.2%).