Full Genome Sequencing of Corriparta Virus, Identifies California Mosquito Pool Virus as a Member of the Corriparta virus Species

Abstract

The species Corriparta virus (CORV), within the genus Orbivirus, family Reoviridae, currently contains six virus strains: corriparta virus MRM1 (CORV-MRM1); CS0109; V654; V370; Acado virus and Jacareacanga virus. However, lack of neutralization assays, or reference genome sequence data has prevented further analysis of their intra-serogroup/species relationships and identification of individual serotypes. We report whole-genome sequence data for CORV-MRM1, which was isolated in 1960 in Australia. Comparisons of the conserved, polymerase (VP1), sub-core-shell ‘T2’ and core-surface ‘T13’ proteins encoded by genome segments 1, 2 and 8 (Seg-1, Seg-2 and Seg-8) respectively, show that this virus groups with the other mosquito borne orbiviruses. However, highest levels of nt/aa sequence identity (75.9%/91.6% in Seg-2/T2: 77.6%/91.7% in Seg-8/T13, respectively) were detected between CORV-MRM1 and California mosquito pool virus (CMPV), an orbivirus isolated in the USA in 1974, showing that they belong to the same virus species. The data presented here identify CMPV as a member of the Corriparta virus species and will facilitate identification of additional CORV isolates, diagnostic assay design and epidemiological studies.

Full Genome Characterization of the Culicoides-Borne Marsupial Orbiviruses: Wallal Virus, Mudjinbarry Virus and Warrego Viruses

“…The G+C content of the WALV, MUDV and WARV genomes are 39.14%, 39.41% and 38.99% respectively, well within the range previously identified for insect-borne orbiviruses (IBOs) (36.66% in PHSV to 45.86% in EEV) but less than tick-borne orbiviruses (TBOs) (51.93% in St Croix River virus (SCRV) to 57.29% in Great Island virus (GIV)) [5] .…”

“…Collectively the upstream and downstream terminal NCRs represent 4.29%, 4.3% and 4.08% of the WALV, MUDV and WARV genomes respectively. Comparisons with other CBOs showed similar or higher percentages, while the mosquito-borne orbiviruses (MBOs) and TBOs show higher values [5] .…”

“…However, Seg-8 (encoding the viral inclusion body protein NS2) of WALV and MUDV, and Seg-5 (encoding the viral tubule protein NS1) of WARV have longer 5′ NCRs ( Table 1 ). Exceptions were also observed in Umatilla virus (UMAV), Corriparta virus (CORV) and GIV, although the significance of these variations is uncertain [5] . Collectively the upstream and downstream terminal NCRs represent 4.29%, 4.3% and 4.08% of the WALV, MUDV and WARV genomes respectively.…”

“…Orbivirus outer capsid protein (OC1) determines virus serotype and is highly variable, both in sequence identity levels and in size. VP2(OC1) of the CBOs is encoded by Seg-2 (VP2), by Seg-3 (VP3) of the MBOs and by Seg-4 (VP4) of the TBOs [5] , [18] , [33] . In WALV, MUDV and WARV viruses, VP2(OC1) is encoded by Seg-2, consistent with Culicoides transmission.…”

“…The advent of more rapid and reliable sequencing methods for dsRNA virus genomes has generated data for reference strains of the individual virus species, that can be easily disseminated for phylogenetic comparisons [5] , [19] , [34] , [37] . These data sets now represent a primary tool for the identification and classification of novel orbivirus isolates [25] – [27] , [31] , [55] .…”