Effects of weak acids on proline accumulation in barley leaves: a comparison between abscisic acid and isobutyric acid |
| |
Authors: | P PESCI N BEFFAGNA |
| |
Institution: | Centro di Studio del C.N.R. per la Biologia Cellulare e Molecolare delle Piante. Dipartimento di Biologia dell'Universitàdegli Studi di Milano, Via Celoria 26, 20133 Milano, Italy |
| |
Abstract: | Abstract. When isobutyric acid (IBA) or abscisic acid (ABA) are supplied to leaf sections a similar rapid and marked decrease in the intracellular pH is observed. This acidification is accompanied by an increase in proline level which is about the same for both 3 mol m−3 IBA and 1 mol m−3 ABA treatments. Fusicoccin (FC), known to act at the proton pump level, almost completely suppresses the ABA-induced acidification of the cell sap, whereas it only partially counteracts the acidifying effect of IBA, in particular during short periods of treatment. This effect of FC is paralleled by a similar inhibition of the induced proline accumulation: in fact, FC completely suppresses the ABA-induced increase in proline during short treatment periods, whereas it is only effective in inhibiting the IBA-induced proline accumulation after long treatment periods. These data seem to suggest that the ABA- and IBA-induced changes in proline level might be mediated by changes in the intracellular pH. |
| |
Keywords: | Hordeum vulgare barley proline accumulation abscisic acid isobutyrate fusicoccin proton pump intracellular pH |
|
|