Reducing PHYTOENE SYNTHASE activity fine-tunes the abundance of a cis-carotene-derived signal that regulates the PIF3/HY5 module and plastid biogenesis
© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com.
| Veröffentlicht in: | Journal of experimental botany. - 1985. - 75(2024), 4 vom: 12. Feb., Seite 1187-1204 |
|---|---|
| 1. Verfasser: | |
| Weitere Verfasser: | , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2024
|
| Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't cis-carotene Apocarotenoid signal Arabidopsis CAROTENOID ISOMERASE ORANGE PHYTOENE SYNTHASE photomorphogenesis plastid biogenesis mehr... |
| Zusammenfassung: | © The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com. PHYTOENE SYNTHASE (PSY) is a rate-limiting enzyme catalysing the first committed step of carotenoid biosynthesis, and changes in PSY gene expression and/or protein activity alter carotenoid composition and plastid differentiation in plants. Four genetic variants of PSY (psy-4, psy-90, psy-130, and psy-145) were identified using a forward genetics approach that rescued leaf virescence phenotypes and plastid abnormalities displayed by the Arabidopsis CAROTENOID ISOMERASE (CRTISO) mutant ccr2 (carotenoid and chloroplast regulation 2) when grown under a shorter photoperiod. The four non-lethal mutations affected alternative splicing, enzyme-substrate interactions, and PSY:ORANGE multi-enzyme complex binding, constituting the dynamic post-transcriptional fine-tuning of PSY levels and activity without changing localization to the stroma and protothylakoid membranes. psy genetic variants did not alter total xanthophyll or β-carotene accumulation in ccr2, yet they reduced specific acyclic linear cis-carotenes linked to the biosynthesis of a currently unidentified apocarotenoid signal regulating plastid biogenesis, chlorophyll biosynthesis, and photomorphogenic regulation. ccr2 psy variants modulated the PHYTOCHROME-INTERACTING FACTOR 3/ELONGATED HYPOCOTYL 5 (PIF3/HY5) ratio, and displayed a normal prolamellar body formation in etioplasts and chlorophyll accumulation during seedling photomorphogenesis. Thus, suppressing PSY activity and impairing PSY:ORANGE protein interactions revealed how cis-carotene abundance can be fine-tuned through holoenzyme-metabolon interactions to control plastid development |
|---|---|
| Beschreibung: | Date Completed 14.02.2024 Date Revised 30.09.2024 published: Print Citation Status MEDLINE |
| ISSN: | 1460-2431 |
| DOI: | 10.1093/jxb/erad443 |