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Abscisic acid (ABA) is an essential plant hormone that regulates multiple aspects of plant development and numerous abiotic stress responses (Cutler et al., 2010; Waadt et al., 2022). In fact, at the heart of plants’ responses to stresses such as salinity, drought, and hypertonic conditions, among others, is this phytohormone (Cutler et al., 2010; Waadt et al., 2022). Interestingly, stress-triggered and developmental responses to this hormone have been found to involve basic RNA metabolism components, including the two subunits of the nuclear cap-binding complex, ABA HYPERSENSITIVE1 (ABH1/CBP80) and CBP20 (Hugouvieux et al., 2001). Additionally, multiple lines of evidence have linked small RNA (smRNA)-mediated RNA silencing to ABA responses (Gregory et al., 2008; Laubinger et al., 2008). A new study by Yan et al. (2025) has provided new insights regarding how RNA degradation and silencing factors modulate smRNA biogenesis from NITRATE REDUCTASE1/2 transcripts to affect ABA-regulated abiotic stress responses.
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Insights into molecular links and transcription networks integrating drought stress and nitrogen signaling
Summary Drought and the availability of nitrate, the predominant source of nitrogen (N) in agriculture, are major factors limiting plant growth and crop productivity. The dissection of the transcriptional networks' components integrating droght stress and nitrate responses provides valuable insights into how plants effectively balance stress response with growth programs. Recent evidence inArabidopsis thalianaindicates that transcription factors (TFs) involved in abscisic acid (ABA) signaling affect N metabolism and nitrate responses, and reciprocally, components of nitrate signaling might affect ABA and drought gene responses. Advances in understanding regulatory circuits of nitrate and drought crosstalk in plant tissues empower targeted genetic modifications to enhance plant development and stress resistance, critical traits for optimizing crop yield and promoting sustainable agriculture.
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- Award ID(s):
- 1840761
- PAR ID:
- 10474478
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 241
- Issue:
- 2
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 560-566
- Size(s):
- p. 560-566
- Sponsoring Org:
- National Science Foundation
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