Completion of molecular characterization of Toscana phlebovirus genome: nucleotide sequence, coding strategy of M genomic segment and its amino acid sequence comparison to other phleboviruses.
The M RNA segment of Toscana (TOS) phlebovirus was cloned and the complete nucleotide sequence determined. The M RNA segment is 4215 nucleotides in length, and it contains a single major open reading frame (ORF) in the viral-complementary sequence, between nucleotides 18 and 4034, which can encode for a polyprotein of 1339 amino acids (Mr 149 kDa). The viral segment is expressed via a unique mRNA containing 10-14 non-templated nucleotides at the 5' end and it is truncated at the 3' end by about 140 nucleotides in a purine-rich region. In M predicted amino acid sequences, several hydrophobic regions have been identified. They could function as a signal sequence or a transmembrane region for the different proteins. Comparison of the deduced amino acid sequence of M precursor product revealed 38, 36, and 25% identity and 58, 56, and 47% similarity with those of Rift Valley fever (RVF), Punta Toro (PT) and Unkuniemi (UUK) viruses, respectively. Residues conserved among the proteins are mainly located at the COOH-portion of the precursor, while the major divergence is in the NSm coding regions. Based on sequence comparison and similarity of hydropathic pattern of TOS M segment with other phleboviruses the N-termini of TOS GN and GC glycoproteins were placed at residues 297 and 936 of the precursor.
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Laboratory of Virology, Istituto Superiore di Sanità, Rome, Italy.
Di Bonito
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Fortini
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Mochi
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Giorgi
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D000595:Amino Acid Sequence; D001483:Base Sequence / Q000235:genetics; D003001:Cloning, Molecular; D016679:Genome, Viral; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D016856:Phlebovirus / Q000737:chemistry* / Q000235:genetics*; D011506:Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014763:Viral Matrix Proteins / Q000235:genetics
D011506:Proteins; D012333:RNA, Messenger; D012367:RNA, Viral; D014763:Viral Matrix Proteins