Disruption of Arabidopsis neutral ceramidases 1 and 2 results in specific sphingolipid imbalances triggering different phytohormone-dependent plant cell death programmes
© 2019 The Authors New Phytologist © 2019 New Phytologist Trust.
| Publié dans: | The New phytologist. - 1979. - 226(2020), 1 vom: 01. Apr., Seite 170-188 |
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| Auteur principal: | |
| Autres auteurs: | , , , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2020
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| Accès à la collection: | The New phytologist |
| Sujets: | Journal Article Research Support, Non-U.S. Gov't jasmonic acid (JA) lipid metabolism neutral ceramidases phytohormone plant defence programmed cell death (PCD) salicylic acid (SA) sphingolipid plus... |
| Résumé: | © 2019 The Authors New Phytologist © 2019 New Phytologist Trust. Sphingolipids act as regulators of programmed cell death (PCD) and the plant defence response. The homeostasis between long-chain base (LCB) and ceramide (Cer) seems to play an important role in executions of PCD. Therefore, deciphering the role of neutral ceramidases (NCER) is crucial to identify the sphingolipid compounds that trigger and execute PCD. We performed comprehensive sphingolipid and phytohormone analyses of Arabidopsis ncer mutants, combined with gene expression profiling and microscopic analyses. While ncer1 exhibited early leaf senescence (developmentally controlled PCD - dPCD) and an increase in hydroxyceramides, ncer2 showed spontaneous cell death (pathogen-triggered PCD-like - pPCD) accompanied by an increase in LCB t18:0 at 35 d, respectively. Loss of NCER1 function resulted in accumulation of jasmonoyl-isoleucine (JA-Ile) in the leaves, whereas disruption of NCER2 was accompanied by higher levels of salicylic acid (SA) and increased sensitivity to Fumonisin B1 (FB1 ). All mutants were also found to activate plant defence pathways. These data strongly suggest that NCER1 hydrolyses ceramides whereas NCER2 functions as a ceramide synthase. Our results reveal an important role of NCER in the regulation of both dPCD and pPCD via a tight connection between the phytohormone and sphingolipid levels in these two processes |
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| Description: | Date Completed 26.04.2021 Date Revised 26.04.2021 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.16336 |