Gibberellins, jasmonate and abscisic acid modulate the sucrose-induced expression of anthocyanin biosynthetic genes in Arabidopsis.
Anthocyanins are secondary metabolites, which play an important role in the physiology of plants. Both sucrose and hormones regulate anthocyanin synthesis. Here, the interplay between sucrose and plant hormones was investigated in the expression of sucrose-regulated genes coding for anthocyanin biosynthetic enzymes in Arabidopsis seedlings. The expression pattern of 14 genes involved in the anthocyanin biosynthetic pathway, including two transcription factors (PAP1, PAP2), was analysed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in Arabidopsis seedlings treated with sucrose and plant hormones. Sucrose-induction of the anthocyanin synthesis pathway was repressed by the addition of gibberellic acid (GA) whereas jasmonate (JA) and abscisic acid (ABA) had a synergic effect with sucrose. The gai mutant was less sensitive to GA-dependent repression of dihydroflavonol reductase. This would seem to prove that GAI signalling is involved in the crosstalk between sucrose and GA in wild-type Arabidopsis seedlings. Conversely, the inductive effect of sucrose was not strictly ABA mediated. Sucrose induction of anthocyanin genes required the COI1 gene, but not JAR1, which suggests a possible convergence of the jasmonate- and sucrose-signalling pathways. The results suggest the existence of a crosstalk between the sucrose and hormone signalling pathways in the regulation of the anthocyanin biosynthetic pathway.
Institute of Biology and Agricultural Biotechnology, CNR, Via del Borghetto 80, 56124, Pisa, Italy.
Elena
E
Loreti
Plant Lab, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, I-56127 Pisa, Italy.
Giovanni
G
Povero
Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, I-56124 Pisa, Italy.
Giacomo
G
Novi
Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, I-56124 Pisa, Italy.
Cinzia
C
Solfanelli
Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, I-56124 Pisa, Italy.
Amedeo
A
Alpi
Plant Lab, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, I-56127 Pisa, Italy.
Pierdomenico
P
Perata
D000040:Abscisic Acid / Q000378:metabolism / Q000494:pharmacology; D000872:Anthocyanins / Q000096:biosynthesis*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005875:Gibberellins / Q000378:metabolism / Q000494:pharmacology; D054883:Oxylipins / Q000378:metabolism / Q000494:pharmacology; D000073718:Pancreatitis-Associated Proteins; D010937:Plant Growth Regulators / Q000378:metabolism* / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D013395:Sucrose / Q000378:metabolism*
D000872:Anthocyanins; D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D005875:Gibberellins; D054883:Oxylipins; D000073718:Pancreatitis-Associated Proteins; D010937:Plant Growth Regulators; C000612141:REG3A protein, human; D012333:RNA, Messenger; D013395:Sucrose; C011006:jasmonic acid; D000040:Abscisic Acid