Habituation of Bean (Phaseolus vulgaris) Cell Cultures to Quinclorac and Analysis of the Subsequent Cell Wall Modifications

• Published in: Annals of botany 2008-06, Vol.101 (9), p.1329-1339
• Main Authors: Alonso-Simón, Ana, García-Angulo, Penélope, Encina, Antonio, Acebes, José Luis, Álvarez, Jesús
• Format: Article
• Language: English
• Subjects: Biosynthesis; cell culture habituation; Cell culture techniques; Cell growth; Cell lines; Cell Wall - chemistry; Cell Wall - drug effects; Cell Wall - metabolism; Cell wall components; Cell walls; Cells, Cultured; cellulose; Cellulose - metabolism; FTIR spectroscopy; Habituation; herbicide; Herbicides; Original; Phaseolus - cytology; Phaseolus - drug effects; Phaseolus - metabolism; Phaseolus vulgaris; Polysaccharides; primary cell wall; Quinclorac; Quinolines - pharmacology; Spectroscopy, Fourier Transform Infrared; Sugars
• ISSN: 0305-7364; 1095-8290
• DOI: 10.1093/aob/mcn051

BACKGROUND AND AIMS: The herbicide quinclorac has been reported to inhibit incorporation of glucose both into cellulose and other cell wall polysaccharides. However, further work has failed to detect any apparent effect of this herbicide on the synthesis of the wall. In order to elucidate whether quinclorac elicits the inhibition of cellulose biosynthesis directly, in this study bean cell calli were habituated to grow on lethal concentrations of the herbicide and the modifications in cell wall composition due to the habituation process were analysed. METHODS: Fourier transform infrared spectroscopy associated with multivariate analysis, cell wall fractionation techniques, biochemical analyses and the immunolocation of different cell wall components with specific monoclonal antibodies were used to characterize the cell walls of quinclorac-habituated cells. KEY RESULTS: Quinclorac-habituated cells were more irregularly shaped than non-habituated cells and they accumulated an extracellular material, which was more abundant as the level of habituation rose. Habituated cells did not show any decrease in cellulose content, but cell wall fractionation revealed that changes occurred in the distribution and post-depositional modifications of homogalacturonan and rhamnogalacturonan I during the habituation process. Therefore, since the action of quinclorac on the cell wall does not seem to be due to a direct inhibition of any cell wall component, it is suggested that the effect of quinclorac on the cell wall could be due to a side-effect of the herbicide. CONCLUSIONS: Long-term modifications of the cell wall caused by the habituation of bean cell cultures to quinclorac did not resemble those of bean cells habituated to the well-known cellulose biosynthesis inhibitors dichlobenil or isoxaben. Quinclorac does not seem to act primarily as an inhibitor of cellulose biosynthesis.