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Abstract Plant roots navigate the soil ecosystem with each cell type uniquely responding to environmental stimuli. Below ground, the plant's response to its surroundings is orchestrated at the cellular level, including morphological and molecular adaptations that shape root system architecture as well as tissue and organ functionality. Our understanding of the transcriptional responses at cell type resolution has been profoundly enhanced by studies of the model plant Arabidopsis thaliana. However, both a comprehensive view of the transcriptional basis of these cellular responses to single and combinatorial environmental cues in diverse plant species remains elusive. In this review, we highlight the ability of root cell types to undergo specific anatomical or morphological changes in response to abiotic and biotic stresses or cues and how they collectively contribute to the plant's overall physiology. We further explore interconnections between stress and the temporal nature of developmental pathways and discuss examples of how this transcriptional reprogramming influences cell type identity and function. Finally, we highlight the power of single-cell and spatial transcriptomic approaches to refine our understanding of how environmental factors fine tune root spatiotemporal development. These complex root system responses underscore the importance of spatiotemporal transcriptional mapping, with significant implications for enhanced agricultural resilience.
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The biology of time: dynamic responses of cell types to developmental, circadian and environmental cues
SUMMARY As sessile organisms, plants are finely tuned to respond dynamically to developmental, circadian and environmental cues. Genome‐wide studies investigating these types of cues have uncovered the intrinsically different ways they can impact gene expression over time. Recent advances in single‐cell sequencing and time‐based bioinformatic algorithms are now beginning to reveal the dynamics of these time‐based responses within individual cells and plant tissues. Here, we review what these techniques have revealed about the spatiotemporal nature of gene regulation, paying particular attention to the three distinct ways in which plant tissues are time sensitive. (i) First, we discuss how studying plant cell identity can reveal developmental trajectories hidden in pseudotime. (ii) Next, we present evidence that indicates that plant cell types keep their own local time through tissue‐specific regulation of the circadian clock. (iii) Finally, we review what determines the speed of environmental signaling responses, and how they can be contingent on developmental and circadian time. By these means, this review sheds light on how these different scales of time‐based responses can act with tissue and cell‐type specificity to elicit changes in whole plant systems.
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- Award ID(s):
- 2042159
- PAR ID:
- 10446286
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 109
- Issue:
- 4
- ISSN:
- 0960-7412
- Page Range / eLocation ID:
- p. 764-778
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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