Shrimp Taura syndrome virus: genomic characterization and similarity with members of the genus Cricket paralysis-like viruses.
The single-stranded genomic RNA of Taura syndrome virus (TSV) is 10205 nucleotides in length, excluding the 3' poly(A) tail, and contains two large open reading frames (ORFs) that are separated by an intergenic region of 207 nucleotides. The ORFs are flanked by a 377 nucleotide 5' untranslated region (UTR) and a 226 nucleotide 3' UTR followed by a poly(A) tail. The predicted amino acid sequence of ORF1 revealed sequence motifs characteristic of a helicase, a protease and an RNA-dependent RNA polymerase, similar to the non-structural proteins of several plant and animal RNA viruses. In addition, a short amino acid sequence located in the N-terminal region of ORF1 presented a significant similarity with a baculovirus IAP repeat (BIR) domain of inhibitor of apoptosis proteins from double-stranded DNA viruses and from animals. The presence of this BIR-like sequence is the first reported in a single-stranded RNA virus, but its function is unknown. The N-terminal amino acid sequence of three TSV capsid proteins (55, 40 and 24 kDa) were mapped in ORF2, which is not in the same reading frame as ORF1 and possesses an AUG codon upstream of the structural genes. However, the intergenic region shows nucleotide sequence similarity with those of the genus Cricket paralysis-like viruses, suggesting a similar non-AUG-mediated translation mechanism. The structure of the TSV genome [5' UTR-non-structural proteins-intergenic UTR-structural proteins-3' UTR-poly(A) tail] is similar to those of small insect-infecting RNA viruses, which were recently regrouped into a new virus genus, Cricket paralysis-like viruses.
Mari
Jocelyne
J
UMR 5098, CNRS/IFREMER/UM2, cc080, Place East Bataillon, 34095 Montpellier Cedex 5, France2.|Aquaculture Pathology Group, Department of Veterinary Science and Microbiology, The University of Arizona, 1117 East Lowell Street, Tucson, Arizona 85721, USA1.
Poulos
Bonnie T
BT
Aquaculture Pathology Group, Department of Veterinary Science and Microbiology, The University of Arizona, 1117 East Lowell Street, Tucson, Arizona 85721, USA1.
Lightner
Donald V
DV
Aquaculture Pathology Group, Department of Veterinary Science and Microbiology, The University of Arizona, 1117 East Lowell Street, Tucson, Arizona 85721, USA1.
Bonami
Jean-Robert
JR
UMR 5098, CNRS/IFREMER/UM2, cc080, Place East Bataillon, 34095 Montpellier Cedex 5, France2.
D000595:Amino Acid Sequence; D000818:Animals; D002213:Capsid / Q000145:classification*; D036022:Capsid Proteins; D018076:DNA, Complementary / Q000737:chemistry; D033364:Decapoda / Q000821:virology*; D016679:Genome, Viral; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D010849:Picornaviridae / Q000145:classification* / Q000235:genetics; D012367:RNA, Viral / Q000737:chemistry
D036022:Capsid Proteins; D018076:DNA, Complementary; D012367:RNA, Viral; C120684:capsid protein, Cricket paralysis virus