Genetic mutants defective in stimulus‐induced Ca2+increases have been gradually isolated, allowing the identification of cell‐surface sensors/receptors, such as the osmosensor OSCA1. However, determining the Ca2+‐signaling specificity to various stimuli in these mutants remains a challenge. For instance, less is known about the exact selectivity between osmotic and ionic stresses in the Here, we have developed a method to distinguish the osmotic and ionic effects by analyzing Ca2+increases, and demonstrated that We recorded Ca2+increases induced by sorbitol (osmotic effect, OE) and NaCl/CaCl2(OE + ionic effect, IE) in The osmotic specificity of
Flooding represents a major threat to global agricultural productivity and food security, but plants are capable of deploying a suite of adaptive responses that can lead to short‐ or longer‐term survival to this stress. One cellular pathway thought to help coordinate these responses is via flooding‐triggered Ca2+signaling. We have mined publicly available transcriptomic data from Arabidopsis subjected to flooding or low oxygen stress to identify rapidly upregulated, Ca2+‐related transcripts. We then focused on transporters likely to modulate Ca2+signals. Candidates emerging from this analysis included Knockout mutants in CAX2 is a Ca2+transporter located on the tonoplast, and so these results are consistent with an important role for vacuolar Ca2+transport in the signaling systems that trigger flooding response.
- PAR ID:
- 10469641
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- ISSN:
- 0028-646X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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