Epigenetic modifications have emerged as an important mechanism underlying plant defence against pathogens. We examined the role of JMJ14, a Jumonji (JMJ) domain‐containing H3K4 demethylase The function of JMJ14 in local or systemic defence response was investigated by pathogen growth assays and by analysing expression and H3K4me3 enrichments of key defence genes using qPCR and ChIP‐qPCR. Salicylic acid (SA) and pipecolic acid (Pip) levels were quantified and function of JMJ14 in SA‐ and Pip‐mediated defences was analysed in Col‐0 and JMJ14 positively modulates defence gene expressions and Pip levels in Arabidopsis.
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. The double but not the single mutants show resistance to the fungal pathogen Notably, diminution of H3K4 and H3K36 trimethylation and expression of negative regulators in challenged plants contributes to stress tolerance of the mutants. Mutations in
- Award ID(s):
- 1916893
- NSF-PAR ID:
- 10445327
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 235
- Issue:
- 5
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1957-1976
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary , in local and systemic plant immune responses in Arabidopsis.jmj14 plants.jmj14 mutants were compromised in both local and systemic defences. JMJ14 positively regulates pathogen‐induced H3K4me3 enrichment and expression of defence genes involved in SA‐ and Pip‐mediated defence pathways. Consequently, loss of JMJ14 results in attenuated defence gene expression and reduced Pip accumulation during establishment of systemic acquired resistance (SAR). Exogenous Pip partially restored SAR injmj14 plants, suggesting that JMJ14 regulated Pip biosynthesis and other downstream factors regulate SAR injmj14 plants. -
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