Low H3K27me3 deposition at CYP82E4 determines the nicotinic conversion rate in Nicotiana tabacum
Copyright © 2023 Elsevier Masson SAS. All rights reserved.
Veröffentlicht in: | Plant physiology and biochemistry : PPB. - 1991. - 206(2024) vom: 20. Jan., Seite 108234 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2024
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Zugriff auf das übergeordnete Werk: | Plant physiology and biochemistry : PPB |
Schlagworte: | Journal Article CYP82E4 H3K27me3 Nicotiana tabacum Nicotine conversion Repressive histone modification Nicotine 6M3C89ZY6R Histones Cytochrome P-450 Enzyme System |
Zusammenfassung: | Copyright © 2023 Elsevier Masson SAS. All rights reserved. Nicotine conversion is the process by which nornicotine is synthesized from nicotine. The capacity of a plant to carry out this process is represented by the nicotine conversion rate (NCR), which is defined as the percentage of nornicotine content out of the total nicotine + nornicotine content. Nicotine conversion in tobacco is mediated by CYP82E4. Although there are cultivar-specific differences in NCR, these do not correspond to differences in the CYP82E4 promoter or gene body sequences, and little is known about the underlying regulatory mechanism. Here, we found that histone H3 Lysine 27 trimethylation (H3K27me3) was involved in CYP82E4 expression, functioning as a transcriptional repressor. Compared to a high-NCR near-isogenic line, a low-NCR cultivar showed increased levels of the repressive histone modification markers H3K27me3 and H3K9me3 at CYP82E4. Comparison of histone markers between several cultivars with varying NCRs showed that H3K27me3 and H3K9me3 levels were significantly associated with cultivar-specific differences in NCR. Treatment with the H3K27me3 demethylase inhibitor GSK-J4 increased total H3K27me3 levels and enriched H3K27me3 at the CYP82E4 locus; the increased levels of H3K27me3 further inhibited CYP82E4 expression. Knocking out E(z), an indispensable gene for H3K27me3 formation, decreased H3K27me3 levels at CYP82E4, leading to a more than three-fold increase in CYP82E4 expression. Changes in CYP82E4 expression during leaf senescence and chilling stress were also strongly correlated with H3K27me3 levels. These findings reveal a strong correlation between CYP82E4 expression and histone modifications, and demonstrate an instance of histone-mediated alkaloid regulation for the first time |
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Beschreibung: | Date Completed 14.02.2024 Date Revised 14.02.2024 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1873-2690 |
DOI: | 10.1016/j.plaphy.2023.108234 |