virus (proposed new species name "Tremovirus A") is a
single species in the genus Tremovirus.
The complete genome of avian
encephalomyelitis virus (AEV) has been determined (Marvil et al.,
1999). This revealed AEV to be a member of the Picornaviridae and
consequently it is the first avian picornavirus for which the genome has
been sequenced. Excluding the poly(A) tail the genome comprises 7,032
nucleotides, which is shorter than that of any mammalian picornavirus
sequenced to date. An open reading frame commencing at nucleotide 495 and
terminating at position 6896 (6402 nucleotides) potentially encodes a
polyprotein of 2134 amino acids. The polyprotein sequence has 39% overall
amino acid identity with hepatitis A virus (HAV; genus Hepatovirus),
compared to 19-21% for viruses from the other five picornavirus genera.
Eleven cleavage products were predicted. The highest identity (49%) with HAV
was in the P1 region, encoding the capsid proteins. The 5’ and 3’
untranslated regions (UTRs) comprise 494 and 136 nucleotides, respectively.
The 5’ UTR is the shortest of any picornavirus sequenced to date and, unlike
HAV, it does not contain a long polypyrimidine tract.
EMBL/GenBank/DDBJ accession no.
The species Avian
encephalomyelitis virus consists of a single serotype now named
avian encephalomyelitis virus 1 (AEV-1).
AEV infects chickens, Japanese quail, turkeys,
pheasants (Welchman et al., 2009) and
pigeons (Toplu and Alcigir, 2004).
Ducklings, partridges (Bodin et al.,
1981) and guinea fowl are susceptible to experimental infection.
Symptons: ataxia and
tremor of the head, neck, and limbs.
Two more complete genome sequences have recently become available, one a
strain from China (LSZ;
the other the van Roekel strain (VR;
viruses have been sequenced at the National Key Laboratory of Veterinary,
Harbin Veterinary Research Institute, China.
Bodin, G., Pellerin, J.L., Milon, A.,
Geral, M.F., Berthelot, X. and Lautie, R. (1981). Étude
de la contamination expérimentale du gibier
à plumes (faisans, perdrix rouges, perdrix
grises) par le virus de l’encéphalomyélite
infectieuse aviaire. Revue Médicine Véterinaire
Marvil, P., Knowles, N.J., Mockett, A.M.A.,
Britton, P., Brown, T.D.K. and Cavanagh, D. (1999). Avian encephalomyelitis
virus is a picornavirus and is most closely related to hepatitis A virus.
Journal of General Virology 80: 653 662.
Toplu, N. and Alcigir, G. (2004).
Avian encephalomyelitis in naturally infected pigeons in Turkey. Avian
Pathology 33: 381-386.