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Plants have evolved variable phenotypic plasticity to counteract different pathogens and pests during immobile life. Microbial infection invokes multiple layers of host immune responses, and plant gene expression is swiftly and precisely reprogramed at both the transcriptional level and post-transcriptional level. Recently, the importance of epigenetic regulation in response to biotic stresses has been recognized. Changes in DNA methylation, histone modification, and chromatin structures have been observed after microbial infection. In addition, epigenetic modifications may be preserved as transgenerational memories to allow the progeny to better adapt to similar environments. Epigenetic regulation involves various regulatory components, including non-coding small RNAs, DNA methylation, histone modification, and chromatin remodelers. The crosstalk between these components allows precise fine-tuning of gene expression, giving plants the capability to fight infections and tolerant drastic environmental changes in nature. Fully unraveling epigenetic regulatory mechanisms could aid in the development of more efficient and eco-friendly strategies for crop protection in agricultural systems. In this review, we discuss the recent advances on the roles of epigenetic regulation in plant biotic stress responses.
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Epigenetics Regulates Reproductive Development in Plants
Seed, resulting from reproductive development, is the main nutrient source for human beings, and reproduction has been intensively studied through genetic, molecular, and epigenetic approaches. However, how different epigenetic pathways crosstalk and integrate to regulate seed development remains unknown. Here, we review the recent progress of epigenetic changes that affect chromatin structure, such as DNA methylation, polycomb group proteins, histone modifications, and small RNA pathways in regulating plant reproduction. In gametogenesis of flowering plants, epigenetics is dynamic between the companion cell and gametes. Cytosine DNA methylation occurs in CG, CHG, CHH contexts (H = A, C, or T) of genes and transposable elements, and undergoes dynamic changes during reproduction. Cytosine methylation in the CHH context increases significantly during embryogenesis, reaches the highest levels in mature embryos, and decreases as the seed germinates. Polycomb group proteins are important transcriptional regulators during seed development. Histone modifications and small RNA pathways add another layer of complexity in regulating seed development. In summary, multiple epigenetic pathways are pivotal in regulating seed development. It remains to be elucidated how these epigenetic pathways interplay to affect dynamic chromatin structure and control reproduction.
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- Award ID(s):
- 1715115
- PAR ID:
- 10168812
- Date Published:
- Journal Name:
- Plants
- Volume:
- 8
- Issue:
- 12
- ISSN:
- 2223-7747
- Page Range / eLocation ID:
- 564
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/plants8120564
