Phosphorylation of DPE2 at S786 partially regulates starch degradation
Copyright © 2022 Elsevier Masson SAS. All rights reserved.
| Veröffentlicht in: | Plant physiology and biochemistry : PPB. - 1991. - 193(2022) vom: 15. Dez., Seite 70-77 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2022
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| Zugriff auf das übergeordnete Werk: | Plant physiology and biochemistry : PPB |
| Schlagworte: | Journal Article DPE2 SnRK1 Starch degradation 4 alpha-glucanotransferase EC 2.4.1.25 Maltose 69-79-4 enkephalinamide-Leu, Ala(2)-aminoethyl dimer- 82221-89-4 mehr... |
| Zusammenfassung: | Copyright © 2022 Elsevier Masson SAS. All rights reserved. In plants, transitory starch is synthetized during the day and degraded at night to provide the continuous carbon needed for growth and development. Starch metabolism is highly coordinated, as the starch degradation rate must be coupled to the amount of starch synthetized during the day. Maltose is one of the chloroplastic products obtained from starch degradation, and maltose is exported to the cytosol where disproportionating enzyme-2 (DPE2) is responsible for its metabolism. The amount of DPE2 remained unchanged throughout the day, but its activity notably increased at the end of the day (7 p.m.), suggesting that posttranslational modification drives the mechanism underlying the regulatory activity of this enzyme. Sucrose nonfermenting-related kinase-1 (SnRK1), a protein kinase that controls the activity of several metabolic enzymes, was able to interact and phosphorylate DPE2 at three different residues localized in the α-glucanotransferase domain. This phosphorylation acts as a positive regulator of DPE2, increasing its activity. Complementation of dpe2-deficient mutants with the wild-type (WT) and S786A forms of DPE2 showed that the nonphosphorylated form of DPE2 only partially restored starch degradation, suggesting that phosphorylation at S786 is involved in enzyme regulation |
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| Beschreibung: | Date Completed 16.11.2022 Date Revised 16.11.2022 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1873-2690 |
| DOI: | 10.1016/j.plaphy.2022.10.024 |