Thermoinductive regulation of Gibberellin metabolism in Thlaspi arvense L. I: Metabolism of [2H]-ent-kaurenoic acid and [14C]gibberellin A12-aldehyde

摘要: Field pennycress (Thlaspi arvense L.) is a winter annual crucifer with cold requirement for stem elongation and flowering. In the present study, metabolism of exogenous [2H]-ent-kaurenoic acid (KA) [14C]-gibberellin A12-aldehyde (GA12-aldehyde) was compared in thermo- noninduced plants. Thermoinduction greatly altered both quantitative qualitative aspects [2H]-KA shoot tips. The rate disappearance parent compound much greater thermoinduced Moreover, there 47 times more endogenous KA than tips as determined by combined gas chromatography-mass spectrometry (GC-MS). major metabolite monohydroxylated derivative KA, while tips, glucose ester hydroxy main product. Gibberellin A9 (GA9) only GA which incorporation deuterium detected GC-MS, this observed amount small indicated large dilution GA9. contrast, leaves metabolized into GA20 equally well, although conversion also limited. These results are consistent suggestion (JD Metzger [1990] Plant Physiol 94: 000-000) that to GAs under thermoinductive control tip, site perception temperatures field pennycress. There were essentially no differences or distribution metabolites formed following application [14C]-GA12-aldehyde Thus, apparent regulation probably limited two metabolic steps involved converting GA12-aldehyde.