Determination of the complete nucleotide sequences of RNA1 and RNA2 from greasy grouper (Epinephelus tauvina) nervous necrosis virus, Singapore strain

The complete nucleotide sequences of RNA1 and RNA2 from greasy grouper (Epi nephelus tauvina) nervous necrosis virus (GGNNV), Singapore strain, were de termined. 5'RACE and RNA ligation were used to obtain the complete nucleoti de sequences of the 5' and 3' non-coding regions (NCRs), GGNNV RNA1 was det ermined to be 3103 nt long, containing an ORF of 982 aa, while GGNNV RNA2 w as determined to be 14.33 nt long, containing an ORF of 338 aa, Both GGNNV RNAs are longer than those of other published betanodavirus sequences and t he additional nucleotides were located within the NCRs. Analysis of GGNNV R NA2 revealed that it is closely related to redspotted grouper nervous necro sis virus and that both grouper viruses share the same neutralization epito pe. Predicted domains for six RNA-dependent RNA polymerase motifs and two p utative ORFs (proteins B1 and B2) were confirmed by sequence analysis of GG NNV RNA1.