02968naa a2200241 a 450000100080000000500110000800800410001910000220006024501290008226000090021130000160022049000370023650001800027352019060045370000140235970000150237370000200238870000180240870000200242670000160244670000180246277302460248014668122007-07-27       2004    bl uuuu     u00u1 u    #d1 aALMEIDA, A. M. R.  aBiological and molecular characterization of an isolate of tobacco streak virus isolated from bud blight soybeans in Brazil.  c2004  ap. 229-230.  a(Embrapa Soja. Documentos, 228).  aEditado por Flávio Moscardi, Clara Beatriz Hoffmann-Campo, Odilon Ferreira Saraiva, Paulo Roberto Galerani, Francisco Carlos Krzyzanowski, Mercedes Concordia Carrão-Panizzi.  aSoybean plants with symptoms of dwarfing and bud blight were observed in commercial fields near Wenceslau Braz county, State of Paraná, Brazil. The plants were used for grafting and for mechanical inoculation. Symptoms appeared 10-12 days after the inoculation or grafting and were identical to those observed in the field. Preliminary examination of leaf tissues from diseased plants by electron microscopy revealed the presence of spherical particles ca. 30 nm diameter. The host range and serological tests identified as tobacco streak virus (TSV). Purified virus showed three peaks in sucrose gradient and electron microscopy revealed spherical particles with 30 nm. Coat protein has a Mr of 29.880 kDa determined in SDS-PAGE. Polyclonal antibodies were obtained against this virus. With specific primers designed based on sequence of the TSV (Cornelissen et al., 1984 Nucleic Acids Res: 12, 277-282) a fragment of 1028 nt was RT-PCR amplified, cloned and sequenced. It contained an open reading frame with 717 nt and 238 deduced amino acids, identified and associated to the coat protein and a 3' untranslated region with 287 nucleotides. Sequence comparison of the nucleotides and predicted amino acids with sequence of TSV CP from white clover (GenBank NC003845, CAA25133) showed identities of 81% and 83%, respectively. A putative Zinc-finger motif was found in the coat protein N-terminus and the 3' untranslated region (UTR) revelead a potential stem-loop structure interpersed with AUGC-motifs, a structure which may signal binding of coat protein and activation of genome replication. The phylogenetic analysis grouped thi siolate of TSV and other TSV isolates in the same branch in 96% of the replicates.This is the first report of molecular characterization of tobacco streak virus isolated from soybeans. It is proposed that this isolate be considered a strain of TSV and named TSV-BR.1 aSAKAI, J.1 aHANADA, K.1 aOLIVEIRA, T. G.1 aBELINTANI, P.1 aKITAJIMA, E. W.1 aNORA, P. S.1 aNOVAES, T. G.  tIn: WORLD SOYBEAN RESEARCH CONFERENCE, 7.; INTERNATIONAL SOYBEAN PROCESSING AND UTILIZATION CONFERENCE, 4.; CONGRESSO BRASILEIRO DE SOJA, 3., 2004, Foz do Iguassu. Abstracts of contributed papers and posters. Londrina: Embrapa Soybean, 2004.