02431nam a2200277Ia 4500003001000000005001700010040000900027245011900036490005500155520147300210650001301683650001801696650003301714650002101747650002201768650003101790700002101821700002001842700001901862700002201881700001601903700001801919700001901937856015601956008004102112MX-MdCICY20260521091620.0  cCICY10aDifferences in phosphatidic acid signalling and metabolism between ABA and GA treatments of barley aleurone cells.0 vPlant physiology and BioChemistry, 65, p.1-8, 20133 aPhosphatidic acid (PA)is the common lipid product in abscisic acid (ABA)and gibberellic acid (GA)response. In this work we investigated the lipid metabolism in response to both hormones. We could detect an in vivo phospholipase D activity (PLD, EC 3.1.4.4). This PLD produced [32P]PA (phosphatidic acid)rapidly (minutes)in the presence of ABA, confirming PA involvement in signal transduction, and transiently, indicating rapid PA removal after generation. The presence of PA removal by phosphatidate phosphatase 1 and 2 isoforms (E.C. 3.1.3.4)was verified in isolated aleurone membranes in vitro, the former but not the latter being specifically responsive to the presence of GA or ABA. The in vitro DGPP phosphatase activity was not modified by short time incubation with GA or ABA while the in vitro PA kinase - that allows the production of 18:2-DGPP from 18:2-PA - is stimulated by ABA. The long term effects (24 h)of ABA or GA on lipid and fatty acid composition of aleurone layer cells were then investigated. An increase in PC and, to a lesser extent, in PE levels is the consequence of both hormone treatments. ABA, in aleurone layer cells, specifically activates a PLD whose product, PA, could be the substrate of PAP1 and/or PAK activities. Neither PLD nor PAK activation can be monitored by GA treatment. The increase in PAP1 activity monitored after ABA or GA treatment might participate in the increase in PC level observed after 24 h hormone incubation.14aALEURONE14aABSCISIC ACID14aDIACYLGLYCEROL PYROSPHOSHATE14aGIBBERELLIC ACID14aPHOSPHATIDIC ACID14aPHOSPHATIDATE PHOSPHATASES12aVillasuso, A. L.12aDi Palma, M. A.12aAveldaño, M.12aPasquaré, S. J.12aRacagni, G.12aGiusto, N. M.12aMachado, E. E.40uhttps://drive.google.com/file/d/1vi4mEm1PE62f_qzZgygnFHWvYwtF-DkH/view?usp=drivesdkzPara ver el documento ingresa a Google con tu cuenta: @cicy.edu.mx250602s9999    xx |||||s2   |||| ||und|d