Regulation of Sugar and Storage Oil Metabolism by Phytochrome during De-etiolation
| Autor: | Hiroyuki Imai, Toshiaki Kozuka, Makoto Kusaba, Masami Yokota Hirai, Shoji Mano, Masatake Kanai, Matsuo Uemura, Mikio Nishimura, Akira Nagatani, Yuji Sawada |
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| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
Light Physiology Arabidopsis Glyoxylate cycle Plant Science Thylakoids 01 natural sciences Phytochrome A Oil body Microscopy Electron Transmission Phytochrome B Etiolation Glyoxysome Genetics Metabolomics Secondary metabolism Chromatography High Pressure Liquid Triglycerides Research Articles Phytochrome biology Arabidopsis Proteins Chemistry Glyoxylates Lipid Droplets biology.organism_classification Glyoxysomes Biochemistry Seedlings Mutation Metabolome Sugars Cotyledon 010606 plant biology & botany |
| Zdroj: | Plant Physiol |
| ISSN: | 1532-2548 0032-0889 |
| DOI: | 10.1104/pp.19.00535 |
| Popis: | Exposure of dark-grown (etiolated) seedlings to light induces the heterotrophic-to-photoautotrophic transition (de-etiolation) processes, including the formation of photosynthetic machinery in the chloroplast and cotyledon expansion. Phytochrome is a red (R)/far-red (FR) light photoreceptor that is involved in the various aspects of de-etiolation. However, how phytochrome regulates metabolic dynamics in response to light stimulus has remained largely unknown. In this study, to elucidate the involvement of phytochrome in the metabolic response during de-etiolation, we performed widely targeted metabolomics in Arabidopsis (Arabidopsis thaliana) wild-type and phytochrome A and B double mutant seedlings de-etiolated under R or FR light. The results revealed that phytochrome had strong impacts on the primary and secondary metabolism during the first 24 h of de-etiolation. Among those metabolites, sugar levels decreased during de-etiolation in a phytochrome-dependent manner. At the same time, phytochrome upregulated processes requiring sugars. Triacylglycerols are stored in the oil bodies as a source of sugars in Arabidopsis seedlings. Sugars are provided from triacylglycerols through fatty acid β-oxidation and the glyoxylate cycle in glyoxysomes. We examined if and how phytochrome regulates sugar production from oil bodies. Irradiation of the etiolated seedlings with R and FR light dramatically accelerated oil body mobilization in a phytochrome-dependent manner. Glyoxylate cycle-deficient mutants not only failed to mobilize oil bodies but also failed to develop thylakoid membranes and expand cotyledon cells upon exposure to light. Hence, phytochrome plays a key role in the regulation of metabolism during de-etiolation. |
| Databáze: | OpenAIRE |
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