Phylogenetic Characterization of the Palyam Serogroup Orbiviruses

Abstract

The Palyam serogroup orbiviruses are associated with abortion and teratogenesis in cattle and other ruminants. Of the 13 different serotypes that have been identified, the full genome sequence of only one, Kasba, has been published. We undertook to perform Next Generation Sequencing (NGS) and phylogenetic analysis on 12 Palyam serotypes plus field isolates of the African serotypes in our possession. The Palyam serogroup was found to be most closely related to the African horse sickness virus group and showed the most distant evolutionary relationship to the equine encephalosis viruses (EEV). Amino acid sequence analysis revealed that the gene encoding VP7 was the most conserved within serotypes and VP2 and VP5 showed the highest degree of variation. A high degree of sequence identity was found for isolates from the same geographical region. The phylogenetic analysis revealed two clades where the African serotypes were all very closely related in one clade and the other clade contained the Australian and Asian serotypes and one African serotype, Petevo. It was evident from the sequence data that the geographical origin of Palyam serogroup viruses played an important role in the development of the different serotypes.

Letea Virus: Comparative Genomics and Phylogenetic Analysis of a Novel Reassortant Orbivirus Discovered in Grass Snakes (Natrix natrix)

“…Interestingly, Tracambé virus (TRV), a serotype of the sand fly-borne CGLV serogroup, was isolated from mosquitoes of the genus Anopheles (Reoviridae.org). Some serotypes of C/SBOV have been isolated from both mosquitoes and biting midges: Eubenangee virus (EUBV) [1,94], Palyam virus (PALV) [1,95], Warrego virus WARV [1], Wongorr virus (WGRV) [1], and Tibet orbivirus (TIBOV) [48]. The associations between some viruses and more than one vector family could be the result of "species jumps" permitted by fast evolution characteristic of RNA segmented viruses.…”

Origin of Bluetongue Virus Serotype 8 Outbreak in Cyprus, September 2016

“…Considering that the %nt identity between Cypriot isolates (99.92-99.95%) was only slightly greater than the %nt identity between Cypriot isolates and their closest relative (ISR2008/13), 98.42-98.45%, the split network constructed here provided an accurate representation of strains originating from separate outbreaks. Although the phylogenetic network is not as common as a tree to display the evolutionary relationship between taxa, it was successfully used for tracing human-to-human transmission during the 2013-2015 Ebola epidemic in Sierra Leone [47], for supporting the field epidemiological investigation during the highly pathogenic avian influenza outbreak in British Columbia [48] or for displaying the geographical relationship amongst the serotypes of the Palyam serogroup of the Orbivirus genus [49]. In the absence of other investigative techniques such as meteorological modelling, the use of phylogenetic networks can be used to determine the origins of BTV strains.…”

Orbiviruses in biting midges and mosquitoes from the Zambezi region, Namibia

“…2c) genes. In all trees, PALV 279-NA-2018 grouped within the Afrotropical clade according to its geographic origin [12]. Growth analyses in C6/36 cells showed the induction of a CPE at four dpi and high genome copy numbers of almost 10 11 copies ml −1 at six dpi (Fig.…”

“…It was first isolated from Culex vishnui mosquitoes in India in 1956 [11]. So far, 13 distinct PALV serotypes have been identified that largely group according to their geographic origin in phylogenetic analyses [12].…”