The fourth genus in the Orthomyxoviridae: sequence analyses of two Thogoto virus polymerase proteins and comparison with influenza viruses.
The tick-borne Thogoto virus (THOV) is the type species of a newly recognized fourth genus, Thogotovirus, in the family Orthomyxoviridae. Because of the distant relationship of THOV with the influenza viruses, determination of its genomic information can potentially be used to identify important domains in influenza virus proteins. We have determined the complete nucleotide sequence of the second longest RNA segment of THOV. The molecule comprises 2212 nucleotides with a single large open reading frame encoding a protein of 710 amino acids, estimated Mr 81,284. The protein shares 77% amino acid similarity with the PB1-like protein of Dhori virus, a related tick-borne virus, and 50-53% with the PB1 polymerase proteins of influenza virus A, B and C. All the motifs characteristic of RNA-dependent polymerases were identified including the SSDD motif common to all RNA-dependent RNA polymerases, indicating that the THOV protein is functionally analogous to the influenza virus PB1 proteins and involved in chain elongation. We also report the corrected sequence of the third longest RNA segment of THOV, encoding a protein which shares 44-47% amino acid similarity with the PA-like polymerase proteins of influenza virus A, B and C. The biological significance of conserved domains in these orthomyxovirid proteins is discussed.
Leahy
M B
MB
NERC Institute of Virology and Environmental Microbiology, Oxford, UK.
Dessens
J T
JT
Weber
F
F
Kochs
G
G
Nuttall
P A
PA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002467:Cell Nucleus / Q000821:virology; D006224:Cricetinae; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism; D009982:Gammainfluenzavirus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009975:Orthomyxoviridae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D018117:Thogotovirus / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
C061290:PA protein, influenza viruses; D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1; D012324:RNA-Dependent RNA Polymerase; D012321:DNA-Directed RNA Polymerases