Dinitroaniline herbicide-resistant transgenic tobacco plants generated by co-overexpression of a mutant alpha-tubulin and a beta-tubulin.
Dinitroaniline herbicides are used for the selective control of weeds in arable crops. Dinitroaniline herbicide resistance in the invasive weed goosegrass was previously shown to stem from a spontaneous mutation in an alpha-tubulin gene. We transformed and regenerated tobacco plants with an alpha/beta-tubulin double gene construct containing the mutant alpha-tubulin gene and showed that expression of this construct confers a stably inherited dinitroaniline-resistant phenotype in tobacco. In all transformed lines, the transgene alpha- and beta-tubulins increased the cytoplasmic pool of tubulin approximately 1.5-fold while repressing endogenous alpha- and beta-tubulin synthesis by up to 45% in some tissues. Transgene alpha- and beta-tubulin were overexpressed in every plant tissue analyzed and comprised approximately 66% of the total tubulin in these tissues. Immunolocalization studies revealed that transgene alpha- and beta-tubulins were incorporated into all four microtubule arrays, indicating that they are functional. The majority of the alpha/beta-tubulin pools are encoded by the transgenes, which implies that the mutant alpha-tubulin and the beta-tubulin can perform the majority, if not all, of the roles of microtubules in both juvenile and adult tobacco plants.
School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK.
R G
RG
Anthony
S
S
Reichelt
P J
PJ
Hussey
D000814:Aniline Compounds / Q000494:pharmacology*; D001549:Benzamides / Q000494:pharmacology; D001709:Biotechnology; D004136:Dinitrobenzenes / Q000494:pharmacology; D004351:Drug Resistance; D006540:Herbicides / Q000494:pharmacology*; D008870:Microtubules / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000187:drug effects*; D010947:Plants, Toxic; D013424:Sulfanilamides; D014026:Nicotiana / Q000187:drug effects* / Q000235:genetics; D014404:Tubulin / Q000235:genetics / Q000378:metabolism*
D000814:Aniline Compounds; D001549:Benzamides; D004136:Dinitrobenzenes; D006540:Herbicides; D013424:Sulfanilamides; D014404:Tubulin; C001059:pronamide; C012465:oryzalin; C030856:pendimethalin