Viruses of invertebrates morphologically and physico-chemically resembling picornaviruses were first recognized in honey bees (Apis mellifera) in the early-1960s (Bailey et al., 1963, 1964). Since that time a plethora of small RNA-containing viruses of invertebrates (many insect) have been described, many of which have been placed in new or existing virus families. Only three of these have officially been recognised as members of the Picornaviridae, cricket paralysis virus (CrPV), Drosophila C virus (DCV) and Gonometa virus. However, there have remained 30-40 viruses which are generally termed 'picorna-like viruses'.

In November 1997 van der Wilk et al. (1997) described the complete nucleotide sequence of Acyrthosiphon pisum virus (APV) which infects the pea aphid. The genome of APV was just over 10 kb in length and contained two slightly overlapping open reading frames (ORFs). The replicative proteins were encoded by ORF-1 (5' end of the genome), while the (three or four) capsid proteins were encoded by ORF-2 (3' end of the genome). The authors postulated that ORF-2 was probably expressed by a -1 translational frameshift, however, a 4 kb subgenomic RNA, derived from the 3' part of the genome was detected in purified virus particles and APV-infected aphids.

Bailey, L., Gibbs, A.J. and Woods, R.D. (1963). Two viruses from adult honey bees (Apis mellifera Linnaeus). Virology 21: 390-395.

Bailey, L., Gibbs, A.J. and Woods, R.D. (1964). Sacbrood virus of the larval honey bee (Apis mellifera Linnaeus). Virology 23: 425-429.

Czibener, C., La Torre, J.L., Muscio, O.A., Ugalde, R.A. and Scodeller, E.A. (2000). Nucleotide sequence analysis of Triatoma virus shows that it is a member of a novel group of insect RNA viruses. J. gen. Virol. 81: 1149-1154.

Ghosh, R.C., Ball, B.V., Willcocks, M.M. and Carter, M.J. (1999). The nucleotide sequence of sacbrood virus of the honey bee: an insect picorna-like virus. J. Gen. Virol. 80: 1541-1549.

Isawa, H., Asano, S., Sahara, K., Iizuka, T. and Bando, H. (1998). Analysis of genetic information of an insect picorna-like virus, infectious flacherie virus of silkworm: evidence for evolutionary relationships among insect, mammalian and plant picorna(-like) viruses. Arch. Virol. 143: 127-143.

Johnson, K.N. and Christian, P.D. (1998). The novel genome organization of the insect picorna-like virus, Drosophila C virus, suggests this virus belongs to a previously undescribed virus family. J. Gen. Virol. 79: 191-203.

King, L.A., Pullin, J.S.K., Stanway, G., Almond, J.W., Moore, N.F. (1987). Cloning of the genome of cricket paralysis virus: Sequence of the 3' end. Virus Res. 6: 331-344.

Koonin, E.V. and Gorbalenya, A.E. (1992). An insect picornavirus may have genome organization similar to that of caliciviruses. FEBS Lett. 297: 81-86.

Leat, N., Ball, B., Govan, V. and Davison, S. (2000). Analysis of the complete genome sequence of black queen-cell virus, a picorna-like virus of honey bees. J. Gen. Virol. 81: 2111-2119.

Moon, J.S., Domier, L.L., McCoppin, N.K., D'Arcy, C.J. and Jin, H. (1998). Nucleotide sequence analysis shows that Rhopalosiphum padi virus is a member of a novel group of insect-infecting RNA virus. Virology 243: 54-65.

Sasaki, J., Nakashima, N., Saito, H. and Noda, H. (1998). An insect picorna-like virus, Plautia stali intestine virus, has genes of capsid proteins in the 3' part of the genome. Virology 244: 50-58.

Tate, J., Liljas, L., Scotti, P., Christian, P., Lin, T. and Johnson, J.E. (1999). The crystal structure of cricket paralysis virus: the first view of a new virus family. Nat. Struct. Biol. 6: 765-774.

van der Wilk, F., Dullemans, A.M., Verbeek, M., Van den Heuvel, J.F.J.M. (1997). Nucleotide sequence and genomic organization of Acyrthosiphon pisum virus. Virology 238: 353-362.

Wilson, J.E., Powell, M.J., Hoover, S.E. and Sarnow P. (2000). Naturally occurring dicistronic cricket paralysis virus RNA is regulated by two internal ribosome entry sites. Mol. Cell. Biol. 20: 4990-4999.