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10:12
Measuring Spatial and Temporal Ca2+ Signals in Arabidopsis Plants
Published on: September 2, 2014
A cell surface receptor mediates extracellular Ca(2+) sensing in guard cells
Shengcheng Han1, Ruhang Tang, Lisa K Anderson
1Department of Biology, Developmental, Cell, and Molecular Biology Group, Duke University, Durham, North Carolina 27708, USA.
Nature
|September 12, 2003
Summary
Plants utilize a novel calcium-sensing receptor (CAS) to monitor extracellular calcium (Ca2+o). This receptor is crucial for regulating calcium homeostasis and plant development, particularly in guard cells.
Area of Science:
- Plant Physiology
- Molecular Biology
- Biochemistry
Background:
- Extracellular calcium (Ca2+o) is vital for plant physiological and developmental processes.
- Plants maintain internal calcium homeostasis despite external fluctuations, implying sophisticated sensing mechanisms.
- The existence and nature of plant Ca2+o-sensing receptors remain largely unknown.
Purpose of the Study:
- To identify plant receptors responsible for sensing extracellular calcium (Ca2+o).
- To investigate the role of such receptors in calcium signaling and plant responses.
- To characterize the function and localization of a newly identified Ca2+o-sensing receptor.
Main Methods:
- Functional screening assay in mammalian cells to isolate Arabidopsis cDNA.
- Localization studies of the identified receptor (CAS) within plant cells.
- Analysis of CAS function by studying its effects on calcium signaling and plant phenotypes.
Main Results:
- An Arabidopsis cDNA clone encoding a calcium-sensing receptor (CAS) was isolated.
- CAS is a plasma membrane-localized protein with low-affinity, high-capacity Ca2+ binding.
- CAS mediates extracellular calcium-induced increases in cytosolic calcium ([Ca2+]i), particularly in guard cells.
Conclusions:
- CAS is identified as a primary transducer of extracellular calcium (Ca2+o) in plants.
- CAS plays a significant role in Ca2+o signaling in guard cells and plant development.
- Disruption of CAS function impairs plant responses to calcium deficiency.
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