title: Mesophyll-localized phytochromes gate stress- and light-inducible anthocyanin accumulation in Arabidopsis thaliana.
abstract: Abiotic stress and light induce anthocyanin accumulation in Arabidopsis. Here, we demonstrate that mesophyll-localized phytochromes regulate nitrogen-, phosphate- and cold-induced anthocyanin accumulation in shoots of Arabidopsis. Whereas ecotype-dependent differences result in distinct total levels of anthocyanin accumulation in response to light, cold, or nutrient-deficient treatments, phytochromes generally gate light- and/or stress-induced anthocyanin accumulation in shoots, as plants depleted of mesophyll-localized phytochromes lack or have highly attenuated induction of anthocyanins. Observed interactions between light and stress were found to be wavelength dependent, with red and far-red light stimulating higher total levels of anthocyanin accumulation under cold temperatures, especially in response to nitrogen limitation, whereas blue light did not. The roots of plants depleted of mesophyll-localized phytochromes still respond to nutrient deficiency as determined by elongation of primary roots and root hair elongation when plants are grown under nitrogen- or phosphate-limited conditions. Plants which are constitutively deficient in photoreceptors in both shoots and roots, i.e., phy or cry mutants, exhibit defects in light- and stress-induced anthocyanin accumulation and defects in root development. Taken together, these results suggest that the response to nutrient limitation in roots and shoots is under distinct control by spatial-specific pools of phytochromes in Arabidopsis.
authors.affiliation: Department of Energy-Plant Research Laboratory; Michigan State University; Plant Biology Laboratories; East Lansing, MI USA.
authors.forename: Sookyung
authors.initials: S
authors.lastname: Oh
authors.affiliation: Department of Energy-Plant Research Laboratory; Michigan State University; Plant Biology Laboratories; East Lansing, MI USA.
authors.forename: Sankalpi N
authors.initials: SN
authors.lastname: Warnasooriya
authors.affiliation: Department of Energy-Plant Research Laboratory; Michigan State University; Plant Biology Laboratories; East Lansing, MI USA; Department of Biochemistry and Molecular Biology; Plant Research Laboratory; Michigan State University; Plant Biology Laboratories; East Lansing, MI USA.
authors.forename: Beronda L
authors.initials: BL
authors.lastname: Montgomery
mesh_terms: D000872:Anthocyanins / Q000378:metabolism*; D017360:Arabidopsis / Q000378:metabolism* / Q000528:radiation effects; D003080:Cold Temperature; D008027:Light; D058503:Mesophyll Cells / Q000378:metabolism*; D009584:Nitrogen; D010710:Phosphates; D010834:Phytochrome / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D000872:Anthocyanins; D010710:Phosphates; D010834:Phytochrome; D009584:Nitrogen
keywords: anthocyanin; cold; nitrogen; nutrient limitation; phosphate; phytochrome