Molecular characterization of beta-tubulin from Phakopsora pachyrhizi, the causal agent of Asian soybean rust

β-tubulins are structural components of microtubules and the targets of benzimidazole fungicides used to control many diseases of agricultural importance. Intron polymorphisms in the intron-rich genes of these proteins have been used in phylogeographic investigations of phytopathogenic fungi. In thi...

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Detalles Bibliográficos
Autores: Maciel, Talles Eduardo Ferreira, Freire, Maíra Cristina Menezes, Almeida, Álvaro M.R. de, Oliveira, Luiz Orlando de
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Brasil
Institución:Universidade Federal de Viçosa (UFV)
Repositorio:LOCUS Repositório Institucional da UFV
Idioma:inglés
OAI Identifier:oai:locus.ufv.br:123456789/12394
Acceso en línea:http://dx.doi.org/10.1590/S1415-47572010005000040
http://www.locus.ufv.br/handle/123456789/12394
Access Level:acceso abierto
Palabra clave:Asian soybean rust
Beta-tubulin
Genetic diversity
Phakopsora pachyrhizi
Soybeans
Descripción
Sumario:β-tubulins are structural components of microtubules and the targets of benzimidazole fungicides used to control many diseases of agricultural importance. Intron polymorphisms in the intron-rich genes of these proteins have been used in phylogeographic investigations of phytopathogenic fungi. In this work, we sequenced 2764 nucleotides of the β-tubulin gene (Pp tubB) in samples of Phakopsora pachyrhizi collected from seven soybean fields in Brazil. Pp tubB contained an open reading frame of 1341 nucleotides, including nine exons and eight introns. Exon length varied from 14 to 880 nucleotides, whereas intron length varied from 76 to 102 nucleotides. The presence of only four polymorphic sites limited the usefulness of Pp tubB for phylogeographic studies in P. pachyrhizi. The gene structures of Pp tubB and orthologous β-tubulin genes of Melampsora lini and Uromyces viciae-fabae were highly conserved. The amino acid substitutions in β-tubulin proteins associated with the onset of benzimidazole resistance in model organisms, especially at His 6 , Glu 198 and Phe 200 , were absent from the predicted sequence of the P. pachyrhizi β-tubulin protein.