A chemical complementation approach reveals genes and interactions of flavonoids with other pathways

Abstract

SUMMARYIn addition to the classical functions of flavonoids in the response to biotic/abiotic stress conditions, these phenolic compounds have been implicated in the modulation of various developmental processes. These findings suggest that flavonoids are more integral components of the plant signaling machinery than traditionally recognized. To understand how flux through the flavonoid pathway affects plant cellular processes, we used wild-type and chalcone isomerase mutant (transparent testa 5, tt5) seedlings grown under anthocyanin inductive conditions, in the presence or absence of the flavonoid intermediate naringenin, the product of the chalcone isomerase enzyme. Because flavonoid biosynthetic genes are expressed under anthocyanin inductive conditions regardless of whether anthocyanins are formed or not, this system provides an excellent opportunity to specifically investigate the molecular changes associated with increased flux through the flavonoid pathway. By assessing genome-wide mRNA accumulation changes in naringenin-treated and untreated tt5 and wild-type seedlings, we identified a flavonoid-responsive gene set associated with cellular trafficking, stress responses and cellular signaling. Jasmonate biosynthetic genes were highly represented among the signaling pathways induced by increased flux through the flavonoid pathway. In contrast to studies showing a role for flavonoids in the control of auxin transport, no effect on auxinresponsive genes was observed. Taken together, our data suggest that Arabidopsis can sense flavonoids as a signal for multiple fundamental cellular processes.

The Identification of Maize and Arabidopsis Type I FLAVONE SYNTHASEs Links Flavones with Hormones and Biotic Interactions

“…For example, in Arabidopsis, jasmonate biosynthetic genes are highly induced when there is an increased flux through the flavonoid pathway (Pourcel et al, 2013), while mutants in the CHALCONE SYNTHASE gene display an elevated auxin transport in young seedlings, roots, and inflorescences (Buer and Muday, 2004). Thus, it was proposed that flavonoids could function as buffering molecules under biotic and abiotic stress conditions (Pourcel et al, 2013).…”

“…For example, in Arabidopsis, jasmonate biosynthetic genes are highly induced when there is an increased flux through the flavonoid pathway (Pourcel et al, 2013), while mutants in the CHALCONE SYNTHASE gene display an elevated auxin transport in young seedlings, roots, and inflorescences (Buer and Muday, 2004). Thus, it was proposed that flavonoids could function as buffering molecules under biotic and abiotic stress conditions (Pourcel et al, 2013). There are at least two different proposed routes for the biosynthesis of salicylic acid, one via the isochorismatic pathway and the second through the Phe ammonium lyase pathway (Dempsey et al, 2011); the flavonoid pathway for the synthesis of apigenin biosynthesis also derives from Phe through the phenylpropanoid biosynthetic pathway.…”

Abiotic stresses induce different localizations of anthocyanins in Arabidopsis

“…Anthocyanins are commonly induced in plant vegetative tissues in response to a number of different abiotic stresses including drought, salinity, excess light, sub-or supra-optimal temperatures, and nitrogen and phosphorous deficiency. [2][3][4][5][6][7][8] The proposed roles of anthocyanins during abiotic stresses include quenching of ROS, 9,10 photoprotection, 11,12 stress signaling, 13,14 and xenohormesis (i.e., the biological principle that relates bioactive compounds in environmentally stressed plants and the increase in stress resistance and survival in animals that feed from them). 15,16 Plants as a group produce hundreds of structurally distinct anthocyanin species.…”

Interaction effects of fructan and Salicylic acid on chickpea in both biochemical and traditional agronomic indicators

“…Other studies also proved that drought tolerant wheat produce and store higher fructan content than drought sensitive wheat during stress (Kerepesi et al, 1998). Pourcel et al 2013 showed that flavonoids play role as signal molecules to adjust responses induced stress conditions. In this study, PAL activities increased twofold under salt stress, and applied pre-treatment in order of increasing PAL activities of the chickpea seedlings were Falone SA-alone < F+SA-combined treatment (maximum 5-fold) under salt stress.…”