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SUMMARY Daily rhythms in physiology are obvious and widespread. While for millennia it was thought that these cycles represent passive responses to environmental cycles, we now recognize that many of them are governed by circadian oscillators. In plants, these cell‐autonomous oscillators regulate daily processes such as photosynthesis, organ growth, and hormone production, as well as seasonal transitions like flowering. Furthermore, the circadian system gates plant responses to biotic and abiotic stresses, modulating susceptibility to pathogens and environmental extremes in a time‐of‐day‐dependent manner. Variants of circadian clock genes have been repeatedly selected during crop domestication and improvement, highlighting the importance of the circadian system to plants and its relevance for agriculture. Here, I review the history of circadian studies in plants and summarize our current understanding of the molecular nature of the circadian oscillator. I also discuss how this complex network both responds to and is buffered against changes in the environment. Next, I examine how circadian oscillators differ between various tissues and how their activities are coordinated throughout the plant body. Finally, I discuss emerging directions, such as ways in which this understanding can be applied to crop improvement in the face of climate change.
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A balancing act: how plants integrate nitrogen and water signals
Abstract Nitrogen (N) and water (W) are crucial inputs for plant survival as well as costly resources for agriculture. Given their importance, the molecular mechanisms that plants rely on to signal changes in either N or W status have been under intense scrutiny. However, how plants sense and respond to the combination of N and W signals at the molecular level has received scant attention. The purpose of this review is to shed light on what is currently known about how plant responses to N are impacted by W status. We review classic studies which detail how N and W combinations have both synergistic and antagonistic effects on key plant traits, such as root architecture and stomatal aperture. Recent molecular studies of N and W interactions show that mutations in genes involved in N metabolism affect drought responses, and vice versa. Specifically, perturbing key N signaling genes may lead to changes in drought-responsive gene expression programs, which is supported by a meta-analysis we conduct on available transcriptomic data. Additionally, we cite studies that show how combinatorial transcriptional responses to N and W status might drive crop phenotypes. Through these insights, we suggest research strategies that could help to develop crops adapted to marginal soils depleted in both N and W, an important task in the face of climate change.
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- Award ID(s):
- 1840761
- PAR ID:
- 10231630
- Editor(s):
- Xu, Guohua
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 71
- Issue:
- 15
- ISSN:
- 0022-0957
- Page Range / eLocation ID:
- 4442 to 4451
- 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/10.1093/jxb/eraa054
