Gibberellins, jasmonate and abscisic acid modulate the sucroseinduced expression of anthocyanin biosynthetic genes in
Arabidopsis
1
3
2
3
3
Giovanni Povero , Elena Loreti , Giacomo Novi , Cinzia Solfanelli , Amedeo Alpi and Pierdomenico Perata
1
1
Plant Lab, Scuola Superiore Sant’Anna, Piazza Martiri della Libertà 33, I–56127 Pisa, Italy; 2Institute of Biology and Agricultural
3
Biotechnology, CNR, Via del Borghetto 80, 56124, Pisa, Italy; Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34,
I–56124 Pisa
SHIKIMATE
PATHWAY
PHENYLALANINE
Summary - Anthocyanins are secondary metabolites, which play
an important role in the physiology of plants. They provide
pigmentation in flowers, fruits, seeds and leaves and are
considered antioxidant molecules. Anthocyanins are also known to
have nutrient and health benefits for humans.
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 results suggest the existence of a crosstalk between the
sucrose and hormone signalling pathways in the regulation of the
ACETATE
PAL
GA3
JA
ABA
C
S
H S+H
REL
low 㻌 㻌 㻌 㻌 㻌 high
CINNAMATE
C4H
GA3
JA
ABA
C
S
H S+H
4-COUMARATE
4CL
GA3
JA
ABA
C
S
H S+H
4-COUMAROYL-COA
S
H S+H
GA3
JA
ABA
NARINGENIN CHALCONE
200 0-
C
S+H
CC SS HH S+H
GA3
JA
ABA
S
GA3
JA
ABA
C
S
UF3GT
KAEMPFEROL
KAEMPFEROL
3-GLUCOSIDE
F3’5’H
DIHYDROMIRICETIN
DFR
DFR
on
tro
Su l
G Gc
A3 A
+S 3
u
AB A c
A+ BA
Su
c
BA B
+S A
u
AC A c
C CC
+S
u
2, 2, c
4D 4D
+S
uc
JA J
+S A
uc
S H S+H
H S+H
DIHYDROQUERCITIN
C
S H S+H
DIHYDROKAEMPFEROL
C
0
C
FLS
GA3
JA
ABA
F3H
GA3
JA
ABA
F3’H
400 -
S H S+H
GA3
JA
ABA
H S+H
NARINGENIN
Gibberellins (GA3) counteract the sucrose
induction of DFR expression, whereas
jasmonate (JA) and abscisic acid (ABA) had
a synergic effect with sucrose enhancing the
induction of the DFR gene
DFR
S
DFR
Relative Expression Level
C
600 -
C
CHI
GA3
JA
ABA
PAP2
C
PAP1
MALONYYL-COA
CHS
GA3
JA
ABA
H S+H
LEUCOPELARGONIDIN LEUCOCYANIDIN
LEUCODELPHYNIDIN
LDOX
GA3
JA
ABA
C
S
H S+H
C
S
H S+H
GA3
JA
ABA
AAT
GA3
JA
ABA
UF3GT
c
Sucrose-treated Arabidopsis seedlings
JA
+S
uc
AB
A+
Su
+S
u
c
G
A3
Su
l
tro
C
on
c
PELARGONIDIN
CYANIDIN
DELPHYNIDIN
C
S
H S+H
600
60 -
The gai mutant is less sensitive to GA-dependent
repression of DFR gene
Ler
gai
400
40 -
-
100
0
C
JA
+S
uc
JA
tro
l
Su
c
C
on
c
JA
Su
JA
+
tro
tro
Su l
AB A c
A+ BA
C Suc
on
tro
Su l
AB A c
A+ BA
S
C uc
on
tro
Su l
AB A c
A+ B A
Su
c
0
GA3
0
C
on
200
100
JA
coi1-1
200
l
Su
c
G
Relative
Expression Level
A3
on
C
Ler
aba1-3
abi1-1
150
400
Suc
Col-gl
300
COI1, but not JAR1, is required for JAmediated DFR expression
on
Relative
Expression Level
600
200
300
Col-0
jar1-1
600
CYANIDIN-3-[P-COUMAROYL]RUTINOSIDE-5-GLUCOSIDE
An overview of the effect of sucrose and hormones on
anthocyanin biosynthetic pathways is reported. Treatments
were as follows: C, control; S, sucrose; H, hormone; S + H,
sucrose + hormone.
Expression data were visualized using Heatmapper Plus
software (http://bbc.botany.utoronto.ca/ntools/cgibin/
ntools_heatmapper_plus.cgi). REL = Relative Expression Level
+S
u
0
C c
on
t ro
l
Su
c
G GA
A3
3
+S
uc
200
20 tro
l
Su
c
G
A3
Relative
Expression Level
PELARGONIDIN-3-O-GLUCOSIDE
CYANIDIN-3-O-GLUCOSIDE
DELPHYNIDIN-3-O-GLUCOSIDE
The sucrose-driven induction of DFR is not strictly
dependent on the synthesis of ABA.
ABI1 is not required for the effects of ABA on the sucrose
induction anthocyanin pathway
ABA
ANTHO
The ability of plant hormones to modulate the anthocyanin
biosynthetic pathway is highly dependent on the presence of
sucrose acting as a consensus-signalling molecule. It thus
appears that an adequate metabolic status, signalled by the
sugar plant level, is a prerequisite for the action of plant
hormones to regulate anthocyanin accumulation