Emerging vesiculo-type virus infections of freshwater fishes in Europe

Diseases of Aquatic Organisms

K. Way¹  A. Benmansour¹  A. M. Betts¹  D. M. Stone¹  C. Torhy¹  P. de Kinkelin¹  S. Chilmonczyk¹ 

关键词: Fish;    Rhabdovirus;    Percids;    Centrarchids;    Thymallids;    Antigenicity;    Proteins;    L gene;   

DOI  :  10.3354/dao057201

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Rhabdoviruses were isolated from perch Perca fluviatilis and largemouth bass Micropterus salmoides exhibiting clinical signs of disease. Preliminary studies indicated that these viruses could be neutralised by antisera to perchrhabdovirus (Dorson et al. 1984) and may be similar to those previously isolated from grayling Thymallus thymallus and pike-perch Stizostedion stizostedion. The relationship between these viruses and the previously characterised fishrhabdoviruses, pike fry rhabdovirus (PFRV), spring viraemia of carp virus (SVCV) and lake trout rhabdovirus, was investigated. Viruses were propagated in bluegill fry (BF-2) cells and were characterised using electron microscopy, serum neutralisationtests, immunofluorescence tests, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and nucleotide sequence analysis. The bullet-shaped viral particles appeared to be compact, with spikes visible at the surface, a morphology similar tothat of the vesiculovirus group of rhabdoviruses. Serum neutralisation tests showed that the viruses were antigenically closely related to the previously characterised perch rhabdovirus, but were not significantly neutralised by antisera to PFRV, SVCV orviral haemorrhagic septicaemia virus (VHSV). In immunofluorescence tests with perch rhabdovirus antisera, strong specific fluorescence was observed in cell cultures infected with the new rhabdovirus isolates, but no fluorescence was observed with antiserato PFRV, SVCV or VHSV. SDS-PAGE analysis revealed a polypeptide profile typical of vesiculoviruses, but the novel virus isolates had different relative mobilities of their P and M proteins compared to PFRV and SVCV. Nucleotide sequence analysis wascarried out using reverse transcriptase-polymerase chain reaction (RT-PCR) and DNA sequencing of a 439 base-pair region of the viral L gene. The novel rhabdovirus isolates had <76% nucleotide sequence identity to PFRV, SVCV and lake trout rhabdovirusand >95% identity to perch rhabdovirus. Phylogenetic analysis using both maximum parsimony and neighbour-joining methods assigned the perch rhaboviruses to a separate group to that of PFRV, SVCV and lake trout rhabdovirus. These data are the initialcharacterisation of a group of emerging fish vesiculo-type viruses that are biochemically and genetically distinct from the PFRV, SVCV and lake trout rhabdoviruses.

【 授权许可】

Unknown