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Summary A dynamic assembly of nuclear and cytoplasmic processes regulate gene activity. Hypoxic stress and the associated energy crisis activate a plurality of regulatory mechanisms including modulation of chromatin structure, transcriptional activation and post‐transcriptional processes. Temporal control of genes is associated with specific chromatin modifications and transcription factors. Genome‐scale technologies that resolve transcript subpopulations in the nucleus and cytoplasm indicate post‐transcriptional processes enable cells to conserve energy, prepare for prolonged stress and accelerate recovery. Moreover, the harboring of gene transcripts associated with growth in the nucleus and macromolecular RNA–protein complexes contributes to the preferential translation of stress‐responsive gene transcripts during hypoxia. We discuss evidence of evolutionary variation in integration of nuclear and cytoplasmic processes that may contribute to variations in flooding resilience.
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Primed to persevere: Hypoxia regulation from epigenome to protein accumulation in plants
Abstract Plant cells regularly encounter hypoxia (low-oxygen conditions) as part of normal growth and development, or in response to environmental stresses such as flooding. In recent years, our understanding of the multi-layered control of hypoxia-responsive gene expression has greatly increased. In this Update, we take a broad look at the epigenetic, transcriptional, translational, and post-translational mechanisms that regulate responses to low-oxygen levels. We highlight how a network of post-translational modifications (including phosphorylation), secondary messengers, transcriptional cascades, and retrograde signals from the mitochondria and endoplasmic reticulum (ER) feed into the control of transcription factor activity and hypoxia-responsive gene transcription. We discuss epigenetic mechanisms regulating the response to reduced oxygen availability, through focussing on active and repressive chromatin modifications and DNA methylation. We also describe current knowledge of the co- and post-transcriptional mechanisms that tightly regulate mRNA translation to coordinate effective gene expression under hypoxia. Finally, we present a series of outstanding questions in the field and consider how new insights into the molecular workings of the hypoxia-triggered regulatory hierarchy could pave the way for developing flood-resilient crops.
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- Award ID(s):
- 1922642
- PAR ID:
- 10561703
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Plant Physiology
- Volume:
- 197
- Issue:
- 1
- ISSN:
- 0032-0889
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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