Striped jack nervous necrosis virus (SJNNV), which infects fish, is the type species of the genus Betanodavirus. This virus has a bipartite genome of positive-strand RNAs, designated RNAs 1 and 2. A small RNA (ca. 0.4 kb) has been detected from SJNNV-infected cells, which was newly synthesized and corresponded to the 3'-terminal region of RNA1.