title: Complete nucleotide sequence of the rice tungro spherical virus genome of the highly virulent strain Vt6.
abstract: The complete nucleotide sequence of rice tungro spherical virus (RTSV) strain Vt6, originally from Mindanao, the Philippines, with higher virulence to resistant rice cultivars, was determined and compared with the published sequence for the Philippine-type strain A (RTSV-A-Shen). It was reported that RTSV-A was not able to infect a rice resistant cultivar TKM 6 (10). RTSV-Vt6 and RTSV-A-Shen share 90% and 95% homology at nucleotide and amino-acid levels, respectively. The N-terminal leader sequence of RTSV-Vt6 contained a 39-amino acids-region (positions 65 to 103) which was totally different from that of RTSV-A-Shen; the difference resulted from frame shifting by nucleotide insertions and deletions. To confirm the amino-acid sequence differences of the leader polypeptide, the same region was cloned and sequenced using a newly obtained variant of RTSV-type 6, which had been collected in the field of IRRI, and seven field isolates from Mindanao, the Philippines. Since all the sequences of the target region are identical to that of the Vt6 leader polypeptide, the sequence difference in the leader region seems not to correlate with the virulence of Vt6.
authors.affiliation: Plant Pathology Laboratory, Faculty of Agriculture, Iwate University, Morioka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Isogai
authors.forename: P Q
authors.initials: PQ
authors.lastname: Cabauatan
authors.forename: C
authors.initials: C
authors.lastname: Masuta
authors.forename: I
authors.initials: I
authors.lastname: Uyeda
authors.forename: O
authors.initials: O
authors.lastname: Azzam
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004279:DNA, Viral / Q000032:analysis; D016679:Genome, Viral; D008969:Molecular Sequence Data; D012275:Oryza / Q000821:virology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014774:Virulence; D019193:Waikavirus / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity
chemical_list: D004279:DNA, Viral