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Summary Histone lysine methylations (HLMs) are implicated in control of gene expression in different eukaryotes. However, the role of HLMs in regulating desirable crop traits and the enzymes involved in these modifications are poorly understood.We studied the functions of tomato histone H3 lysine methyltransferases SET Domain Group 33 (SDG33) and SDG34 in biotic and abiotic stress responses.SDG33andSDG34gene edited mutants were altered in H3K36 and H3K4 methylations, and expression of genes involved in diverse processes and responses to biotic and abiotic stimuli.The double but not the single mutants show resistance to the fungal pathogenBotrytis cinerea.Interestingly, single mutants were tolerant to drought and the double mutant showed superior tolerance and plant growth consistent with independent and additive functions. Mutants maintained higher water status during drought and improved recovery and survival after lapse of drought.Notably, diminution of H3K4 and H3K36 trimethylation and expression of negative regulators in challenged plants contributes to stress tolerance of the mutants. Mutations inSDG33andSDG34are likely to remove predisposition to biotic and abiotic stress by disrupting permissive transcriptional context promoting expression of negative regulatory factors. These allows improvement of stress and pathogen tolerance, without growth trade‐offs, through modification of histone epigenetic marks.
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Silencing ZmPP2C‐A10 with a foxtail mosaic virus (FoMV) derived vector benefits maize growth and development following water limitation
Abstract Global climate change is causing more frequent and severe droughts, which can have negative impacts on plant growth and crop productivity. Under drought conditions, plants produce the hormone ABA (abscisic acid), which regulates adaptive responses, such as stomatal closure and root elongation. Plant viruses have been used in the lab to convey new traits to plants and could also be used to increase production of ABA or to enhance downstream plant drought resistance responses.In this study, foxtail mosaic virus (FoMV) was used to silenceZmPP2C‐A10, a negative regulator of ABA signalling, in maize (Zea maysL.). Both silenced and control plants were exposed to an 8‐day drought treatment, followed by a 30‐day period of rewatering, after which indicators of drought resistance were measured.After drought treatment, we observed a nearly twofold increase in expression of a stress‐mitigation gene,ZmRAB17, reduced chlorophyll fluorescence changes (indicator of stress), and increased plant biomass and development in theZmPP2C‐A10‐silenced maize compared to controls.These results demonstrate that the FoMV system can be used to silence endogenous expression ofZmPP2C‐A10and increase maize tolerance to drought. This could offer a useful tool to improve crop traits and reduce yield loss during the growing season.
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- Award ID(s):
- 2026068
- PAR ID:
- 10464059
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Plant Biology
- Volume:
- 25
- Issue:
- 6
- ISSN:
- 1435-8603
- Page Range / eLocation ID:
- p. 956-964
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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