RESUMEN
The phenoxy herbicides (e.g., 2,4-D and MCPA) are used widely in agriculture for the selective control of broadleaf weeds. In Western Australia, the reliance on phenoxy herbicides has resulted in the widespread evolution of phenoxy resistance in wild radish (Raphanus raphanistrum) populations. In this research the inheritance and mechanism of MCPA resistance in wild radish were determined. Following classical breeding procedures, F1, F2, and backcross progeny were generated. The F1 progeny showed an intermediate response to MCPA, compared to parents, suggesting that MCPA resistance in wild radish is inherited as an incompletely dominant trait. Segregation ratios observed in F2 (3:1; resistant:susceptible) and backcross progeny (1:1; resistant to susceptible) indicated that the MCPA resistance is controlled by a single gene in wild radish. Radiolabeled MCPA studies suggested no difference in MCPA uptake or metabolism between resistant and susceptible wild radish; however, resistant plants rapidly translocated more (14)C-MCPA to roots than susceptible plants, which may have been exuded from the plant. Understanding the genetic basis and mechanism of phenoxy resistance in wild radish will help formulate prudent weed management strategies to reduce the incidence of phenoxy resistance.
Asunto(s)
Ácido 2-Metil-4-clorofenoxiacético/farmacología , Resistencia a los Herbicidas , Herbicidas/farmacología , Raphanus/efectos de los fármacos , Ácido 2-Metil-4-clorofenoxiacético/metabolismo , Cruzamiento , Herbicidas/metabolismo , Raphanus/genética , Raphanus/metabolismo , Australia OccidentalRESUMEN
To study the agricultural production of biosimilar antibodies, trastuzumab (Herceptin) was expressed in Nicotiana benthamiana using the magnICON viral-based transient expression system. Immunoblot analyses of crude plant extracts revealed that trastuzumab accumulates within plants mostly in the fully assembled tetrameric form. Purification of trastuzumab from N. benthamiana was achieved using a scheme that combined ammonium sulfate precipitation with affinity chromatography. Following purification, the specificity of the plant-produced trastuzumab for the HER2 receptor was compared with Herceptin and confirmed by western immunoblot. Functional assays revealed that plant-produced trastuzumab and Herceptin have similar in vitro antiproliferative effects on breast cancer cells that overexpress HER2. Results confirm that plants may be developed as an alternative to traditional antibody expression systems for the production of therapeutic mAbs.
Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/farmacología , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Nicotiana/metabolismo , Receptor ErbB-2/metabolismo , Adenocarcinoma/metabolismo , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales Humanizados , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Reactores Biológicos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Planticuerpos/química , Planticuerpos/genética , Planticuerpos/metabolismo , Planticuerpos/farmacología , Plantas Modificadas Genéticamente/metabolismo , Nicotiana/genética , TrastuzumabRESUMEN
A competitive direct enzyme-linked immunosorbent assay (ELISA) and high-pressure liquid chromatographic (HPLC) methods were compared in terms of accuracy and precision for the detection and quantification of glyphosate-spiked Nanopure, tap, and river waters. The ELISA had a detection limit of 0.6 ng mL(-)(1) and a linear working range of 1-25 ng mL(-)(1), whereas the HPLC method had a detection limit of 50 ng mL(-)(1) and a linear working range of 100-10000 ng mL(-)(l). No statistically significant differences (95% confidence interval) were found between the ELISA and HPLC analysis of the three water matrixes. The coefficients of variation obtained with the ELISA in tap water were between 10 and 19%, whereas the coefficients of variation for the HPLC analysis were between 7 and 15%. The use of ELISA for the analysis of glyphosate in water is a cost-effective and reliable method capable of meeting water quality guidelines established for Europe and North America.
