Brudenell, A. J. P. and Griffiths, H. and Rossiter, J. T. and Baker, D. A. (1999) The phloem mobility of glucosinolates. Journal of Experimental Botany, 50 (335). p. 745. ISSN 0022-0957Full text not available from this repository. (Request a copy)
The transport properties of glucosinolates within Brassica napus are of interest as identification of the mechanism of transport could lead to lower levels being obtained in specific tissues such as the seeds. The phloem mobility of S-35-gluconapin (but-3-enylglucosinolate) and S-35-desulphogluconapin in oilseed rape plants has been inferred from tissue distribution patterns, as well as from observed coincident phloem mobility of H-3-gluconapin and C-14-sucrose, The measured relative phloem mobilities for sinigrin (2-propenylglucosinolate), H-3-gluconapin, 35S-desulphogluconapin, S-35-desulphosinigrin, C-14-tryptophan, H-3-AIB (alpha-aminoisobutyric acid), and literature values for a reduced H-3-oligogalacturonide elicitor (degree of polymerization 6) and C-14-IAA (indolylacetic acid), have been compared with the predicted values obtained using the Kleier model for phloem mobility of xenobiotics. All the above compounds show phloem systemicity, demonstrated using the Ricinus assay, as predicted by the model. Log K-ow (octanol-water partition coefficient) values for glucosinolates and desulphoglucosinolates measured at pH 4 and pH 7, and the effect of pH on uptake by oilseed rape embryos are provided as evidence against a weak acid trap mechanism acting in either the phloem mobility or the accumulation of glucosinolates in oilseed rape embryos. The phloem mobility of glucosinolates is explained by the intermediate permeability hypothesis, In conclusion, it would appear that glucosinolates like other groups of endogenous compounds have physicochemical properties allowing phloem mobility as predicted by the Kleier model.
Biological Sciences > Botany
|Depositing User:||Dr Alistair JP Brudenell|
|Date Deposited:||13 Aug 2012 17:23|
|Last Modified:||13 Aug 2012 17:23|
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