Detection and molecular characterization of a novel piscine-myocarditis-like virus from baitfish in the USA

Abstract

During a survey of apparently healthy baitfish from the state of Minnesota, a novel piscine-myocarditis-like virus (PMCLV) was detected in golden shiners (Notemigonus crysoleucas). The nearly complete genome sequence is 5819 nt long, including a partial 5' untranslated region (UTR) of 100 nt. The sequence is divided into three ORFs: the complete ORF1 and ORF2, encoding proteins of 818 and 831 amino acids, respectively, and a partial ORF3 encoding 248 amino acids of the corresponding protein. This novel virus sequence was most closely related to piscine myocarditis virus (PMCV), with a 49.0 % and 58.2 % amino acid identity in the ORF1 (YP005481249)- and ORF2 (YP004581250)-encoded proteins, respectively. Six of 56 retail outlets (e.g., bait shops) were positive during the 2014-2015 survey, indicating a 10.7 % prevalence of the novel virus in this population of golden shiners. Currently, there is no disease that is known to be associated with this virus.

Cardiomyopathy syndrome in Atlantic salmon Salmo salar L.: A review of the current state of knowledge

“…This protein is believed to represent a RNA‐dependent RNA polymerase (RdRp), based on its position in the genome and similarity to amino acid sequences coding for RdRps found in the Totiviridae (Haugland et al., ). The presence of a third ORF in the genome has been a feature exclusively seen for PMCV, but it has recently also been found in the PMCV‐like virus found in Golden shiner (Mor & Phelps, ). The PMCV ORF3 encoded protein is 302 aa long, with a predicted molecular mass of 33.4 kDa.…”

“…In 2016, two new viruses with similarities to the Totiviridae were found in Golden shiner Notemigonus crysoleucas (Mitchill) baitfish from commercial outlets. One of them had closest genomic similarities to PMCV (Mor & Phelps, ), while the other was closer to arthropod‐infecting toti‐like viruses (Mor & Phelps, ). None of these arthropod‐ or fish‐infecting viruses are yet officially assigned to the virus family.…”

Genetic diversity of piscine myocarditis virus in Atlantic salmon Salmo salar L. in Ireland

“…In addition, the corresponding sequence from seven Irish samples from 2012 (Rodger et al, ) and from 21 Norwegian samples (Haugland et al, ; Wiik‐Nielsen et al, ) were included in the phylogenetic analysis. In order to correctly root the tree generated, the corresponding sequence from piscine myocarditis‐like virus (accession number: ; Mor & Phelps, ) was included in the analysis. Concatenated sequences were aligned using ClustalX2 (Larkin et al, ), and MEGA7 (Kumar et al, ) was used to generate a maximum likelihood phylogenetic tree.…”

“…Piscine myocarditis virus has been classified as a toti‐like virus due to similarities with viruses in the Totiviridae family and was the first toti‐like virus found to infect vertebrates (Garseth, Fritsvold, Svendsen, Bang Jensen, & Mikalsen, ). However, in 2016 two new toti‐like viruses were identified in golden shiner ( Notemigonus crysoleucas Mitchill) (Mor & Phelps, , ). In addition, a unique strain of PMCV has been reported previously from Atlantic argentine Argentina silus (Ascanius, 1775) (Böckerman, Wiik‐Nielsen, Sindre, Johansen, & Tengs, ; Tengs & Böckerman, ).…”

Retail Baitfish in Michigan Harbor Serious Fish Viral Pathogens

“…Fathead minnow picornavirus and WSBV were not detected in this study; however, their pathogenicity and the risk they pose to piscivorous fish need to be assessed. In the same context, molecular evidence has demonstrated the presence of other viruses in a common baitfish species, the Golden Shiner—namely a novel piscine‐myocarditis‐like virus (Mor and Phelps ) and a novel totivirus (Mor and Phelps ). However, the potential pathogenicity of these novel viruses to Golden Shiners or other fish species is currently unknown.…”