Desiccation tolerance has evolved recurrently in grasses using two unique strategies of either protecting or dismantling the photosynthetic apparatus to minimize photooxidative damage under life without water (anhydrobiosis). Here, we surveyed chromatin architecture and gene expression during desiccation in two closely related grasses with distinguishing desiccation tolerance strategies to identify regulatory dynamics underlying these unique adaptations. In both grasses, we observed a strong association between nearby chromatin accessibility and gene expression in desiccated tissues compared to well‐watered, reflecting an unusual chromatin stability under anhydrobiosis. Integration of chromatin accessibility (ATACseq) and expression data (RNAseq) revealed a core desiccation response across these two grasses. This includes many genes with binding sites for the core seed development transcription factor ABI5, supporting the long‐standing hypothesis that vegetative desiccation tolerance evolved from rewiring seed pathways.
Resurrection plants can survive prolonged life without water (anhydrobiosis) in regions with seasonal drying. This desiccation tolerance requires the coordination of numerous cellular processes across space and time, and individual plant tissues face unique constraints related to their function. Here, we analyzed the complex, octoploid genome of the model resurrection plant
- Award ID(s):
- 2213983
- NSF-PAR ID:
- 10405961
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 114
- Issue:
- 2
- ISSN:
- 0960-7412
- Page Range / eLocation ID:
- p. 231-245
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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