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Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Mechanosensitive Ca2+ release from intracellular stores in Nitella flexilis
1Biological Laboratory, The University of the Air, 2-11 Wakaba, Mihama-ku, Chiba, 261-8586 Japan.
Plant & Cell Physiology
|May 3, 2001
Summary
Mechanical stimuli trigger calcium release in Nitella flexilis cells. This hydration-induced calcium release (HICR) is mediated by mechano-sensitive calcium channels, potentially involving chloroplasts or starch grains.
Area of Science:
- Plant cell physiology
- Ion channel mechanosensitivity
- Calcium signaling
Background:
- Nitella flexilis cytoplasmic drops exhibit hydration-induced calcium release (HICR).
- HICR is hypothesized to involve stretch-activated calcium channels in intracellular stores.
Purpose of the Study:
- To investigate the mechanical sensitivity of calcium channels in Nitella flexilis.
- To identify cellular components responsible for mechanical stimulus-induced calcium release.
Main Methods:
- Mechanical stimulation of isolated cytoplasmic drops (hypotonic medium injection, compression).
- Fractionation of cytoplasmic drops into chloroplast and chloroplast-free components.
- Comparative studies using Chara corallina.
Main Results:
- Mechanical stimuli, including compression and medium injection, induced rapid calcium release in Nitella flexilis drops.
- Chloroplast fractions, but not chloroplast-free cytoplasm, released Ca2+ upon compression.
- Addition of chloroplasts or starch grains to chloroplast-free cytoplasm restored mechanosensitivity.
Conclusions:
- Calcium channels in Nitella flexilis intracellular stores are indeed mechano-sensitive.
- Chloroplasts or starch grains may play a role in mediating the mechanical response of these channels.
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