Metabolic profiling and cytological analysis of proanthocyanidins in immature seeds of Arabidopsis thaliana flavonoid accumulation mutants

Although it is well known that phosphate (Pi) deficiency affects flavonoid accumulation in higher plants, knowledge on the regulation and potential function of flavonoids in the plants grown with low Pi supply is lacking. In this work, we found that low Pi treatment caused significant reduction of root flavonoid (e.g. quercetin, kaempferol and their derivatives) levels in both Columbia (Col-0) and Landsberg erecta (Ler) ecotypes of Arabidopsis thaliana (L.) Heynh. Further investigations revealed that the dysfunction of PHR1, PHO1, PHO2 and NPC4 did not affect the decrease of root flavonoid level by low Pi treatment. In contrast, pldζ2, a knockout mutant of the Arabidopsis phospholipase Dζ2, exhibited defects in the reduction of root flavonoid level and lateral root (LR) emergence under low Pi conditions. When grown under low Pi supply, the transport of auxin from the shoot apex into the root, expression of the auxin responsive DR5::GUS marker and induction of the auxin responsive genes were all significantly less efficient in pldζ2 than in wild-type (WT) control. This is the first report on the reduction of root flavonoid level and its likely contribution to increased LR emergence in Arabidopsis under Pi deficiency conditions, which may facilitate the adaptation of plants to the growth environments with poor Pi availability.

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Arabidopsis thaliana G2‐LIKE FLAVONOID REGULATOR and BRASSINOSTEROID ENHANCED EXPRESSION1 are low‐temperature regulators of flavonoid accumulation

New Phytologist ◽

10.1111/nph.13986 ◽

2016 ◽

Vol 211 (3) ◽

pp. 912-925 ◽

Cited By ~ 34

Author(s):

Antonios Petridis ◽

Stefanie Döll ◽

Lars Nichelmann ◽

Wolfgang Bilger ◽

Hans‐Peter Mock

Keyword(s):

Arabidopsis Thaliana ◽

Low Temperature ◽

Flavonoid Accumulation

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Leaf Age-Dependent Photosystem II Photochemistry and Oxidative Stress Responses to Drought Stress in Arabidopsis thaliana Are Modulated by Flavonoid Accumulation

Molecules ◽

10.3390/molecules26144157 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4157

Author(s):

Ilektra Sperdouli ◽

Julietta Moustaka ◽

Georgia Ouzounidou ◽

Michael Moustakas

Keyword(s):

Lipid Peroxidation ◽

Arabidopsis Thaliana ◽

Drought Stress ◽

Photosystem Ii ◽

Stress Responses ◽

Heat Dissipation ◽

Leaf Age ◽

Psii Photochemistry ◽

Young Leaves ◽

Flavonoid Accumulation

We investigated flavonoid accumulation and lipid peroxidation in young leaves (YL) and mature leaves (ML) of Arabidopsis thaliana plants, whose watering stopped 24 h before sampling, characterized as onset of drought stress (OnDS), six days before sampling, characterized as mild drought stress (MiDS), and ten days before sampling, characterized as moderate drought stress (MoDS). The response to drought stress (DS) of photosystem II (PSII) photochemistry, in both leaf types, was evaluated by estimating the allocation of absorbed light to photochemistry (ΦPSII), to heat dissipation by regulated non-photochemical energy loss (ΦNPQ) and to non-regulated energy dissipated in PSII (ΦNO). Young leaves were better protected at MoDS than ML leaves, by having higher concentration of flavonoids that promote acclimation of YL PSII photochemistry to MoDS, showing lower lipid peroxidation and excitation pressure (1 − qp). Young leaves at MoDS possessed lower 1 − qp values and lower excess excitation energy (EXC), not only compared to MoDS ML, but even to MiDS YL. They also possessed a higher capacity to maintain low ΦNO, suggesting a lower singlet oxygen (1O2) generation. Our results highlight that leaves of different developmental stage may display different responses to DS, due to differential accumulation of metabolites, and imply that PSII photochemistry in Arabidopsis thaliana may not show a dose dependent DS response.

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