Glutamate decarboxylase-1 is essential for efficient acclimation of Arabidopsis thaliana to nutritional phosphorus deprivation
© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.
| Veröffentlicht in: | The New phytologist. - 1979. - 240(2023), 6 vom: 14. Dez., Seite 2372-2385 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2023
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Arabidopsis thaliana (thale cress) Pi starvation response glutamate decarboxylase metabolic bypasses phosphorus nutrition γ-aminobutyrate shunt Phosphorus 27YLU75U4W Glutamate Decarboxylase mehr... |
| Zusammenfassung: | © 2023 The Authors New Phytologist © 2023 New Phytologist Foundation. Glutamate decarboxylase (GAD) is a Ca2+ -calmodulin-activated, cytosolic enzyme that produces γ-aminobutyrate (GABA) as the committed step of the GABA shunt. This pathway bypasses the 2-oxoglutarate to succinate reactions of the tricarboxylic acid (TCA) cycle. GABA also accumulates during many plant stresses. We tested the hypothesis that AtGAD1 (At5G17330) facilitates Arabidopsis acclimation to Pi deprivation. Quantitative RT-PCR and immunoblotting revealed that AtGAD1 transcript and protein expression is primarily root-specific, but inducible at lower levels in shoots of Pi-deprived (-Pi) plants. Pi deprivation reduced levels of the 2-oxoglutarate dehydrogenase (2-OGDH) cofactor thiamine diphosphate (ThDP) in shoots and roots by > 50%. Growth of -Pi atgad1 T-DNA mutants was significantly attenuated relative to wild-type plants. This was accompanied by: (i) an > 60% increase in shoot and root GABA levels of -Pi wild-type, but not atgad1 plants, and (ii) markedly elevated anthocyanin and reduced free and total Pi levels in leaves of -Pi atgad1 plants. Treatment with 10 mM GABA reversed the deleterious development of -Pi atgad1 plants. Our results indicate that AtGAD1 mediates GABA shunt upregulation during Pi deprivation. This bypass is hypothesized to circumvent ThDP-limited 2-OGDH activity to facilitate TCA cycle flux and respiration by -Pi Arabidopsis |
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| Beschreibung: | Date Completed 17.11.2023 Date Revised 17.11.2023 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.19300 |