Transcriptional regulation of 9-cis-epoxycarotenoid dioxygenase (NCED) gene by putrescine accumulation positively modulates ABA synthesis and drought tolerance in Lotus tenuis plants.
The accumulation of putrescine (Put) and increased arginine decarboxylase (ADC, EC 4.1.1.19) activity levels in response to osmotic stress has been reported; however, the biological meaning of this increase remains unclear. To obtain new insights into these questions, we studied the drought response of a transgenic Lotus tenuis line that expresses the oat ADC gene, which is driven by the stress-inducible pRD29A promoter. This line contains high levels of Put with no changes in spermidine and spermine contents, even under water deficits. Our results indicate that the biochemical and morphological responses to dehydration correlate with the Put level and provide evidence that Put controls the ABA content in response to drought by modulating ABA biosynthesis at the transcriptional level.
Instituto de Botánica del Nordeste (IBONE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste, Sargento Cabral 2131, CC: 209, W3402BKG Corrientes, Argentina.
Fabiana D
FD
Espasandin
Unidad de Biotecnología 1 IIB-INTECh (CONICET), CC: 164, B7130IWA Chascomús, Argentina.
Santiago J
SJ
Maiale
Unidad de Biotecnología 1 IIB-INTECh (CONICET), CC: 164, B7130IWA Chascomús, Argentina.
Pablo
P
Calzadilla
Unidad de Biotecnología 1 IIB-INTECh (CONICET), CC: 164, B7130IWA Chascomús, Argentina.
Oscar A
OA
Ruiz
Instituto de Botánica del Nordeste (IBONE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste, Sargento Cabral 2131, CC: 209, W3402BKG Corrientes, Argentina. Electronic address: sansber@agr.unne.edu.ar.
Pedro A
PA
Sansberro
D000040:Abscisic Acid / Q000096:biosynthesis*; D017360:Arabidopsis / Q000235:genetics; D049308:Dioxygenases / Q000235:genetics / Q000378:metabolism*; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D000070116:Lotus / Q000378:metabolism*; D053078:Membrane Potential, Mitochondrial; D008564:Membrane Potentials; D009995:Osmosis; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism; D030821:Plants, Genetically Modified; D011392:Proline / Q000737:chemistry; D011700:Putrescine / Q000096:biosynthesis*; D013997:Time Factors; D014158:Transcription, Genetic; D014867:Water
D010940:Plant Proteins; D014867:Water; D000040:Abscisic Acid; D011392:Proline; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase; D011700:Putrescine
Abscisic acid; Arginine decarboxylase; Drought; Lotus tenuis; Polyamines