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To cope with abiotic environmental stress, plants rapidly change their gene expression transcriptionally and post-transcriptionally, the latter by translational suppression of selected proteins and the assembly of cytoplasmic stress granules (SGs) that sequester mRNA transcripts. RNA-binding proteins (RBPs) are the major players in these post-transcriptional processes, which control RNA processing in the nucleus, their export from the nucleus, and overall RNA metabolism in the cytoplasm. Because of their diverse modular domain structures, various RBP types dynamically co-assemble with their targeted RNAs and interacting proteins to form SGs, a process that finely regulates stress-responsive gene expression. This review summarizes recent findings on the involvement of RBPs in adapting plants to various abiotic stresses via modulation of specific gene expression events and SG formation. The relationship of these processes with the stress hormone abscisic acid (ABA) is discussed.
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Conserved and nuanced hierarchy of gene regulatory response to hypoxia
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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- PAR ID:
- 10373483
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 229
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 71-78
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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