As a universal second messenger, calcium (Ca2+) transmits specific cellular signals via a spatiotemporal signature generated from its extracellular source and internal stores. Our knowledge of the mechanisms underlying the generation of a Ca2+ signature is hampered by limited tools for simultaneously monitoring dynamic Ca2+ levels in multiple subcellular compartments. To overcome the limitation and to further improve spatiotemporal resolutions, we have assembled a molecular toolset (CamelliA lines) in Arabidopsis (Arabidopsis thaliana) that enables simultaneous and high-resolution monitoring of Ca2+ dynamics in multiple subcellular compartments through imaging different single-colored genetically encoded calcium indicators. We uncovered several Ca2+ signatures in three types of Arabidopsis cells in response to internal and external cues, including rapid oscillations of cytosolic Ca2+ and apical plasma membrane Ca2+ influx in fast-growing Arabidopsis pollen tubes, the spatiotemporal relationship of Ca2+ dynamics in four subcellular compartments of root epidermal cells challenged with salt, and a shockwave-like Ca2+ wave propagating in laser-wounded leaf epidermis. These observations serve as a testimony to the wide applicability of the CamelliA lines for elucidating the subcellular sources contributing to the Ca2+ signatures in plants.
- Award ID(s):
- 1826803
- NSF-PAR ID:
- 10179209
- Date Published:
- Journal Name:
- Annals of Botany
- Volume:
- 124
- Issue:
- 7
- ISSN:
- 0305-7364
- Page Range / eLocation ID:
- 1227 to 1242
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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