Phytochrome control of electrical potentials and intercellular coupling in oat-coleoptile tissue
1Department of Biology, Yale University, 06520, New Haven, CT, USA.
Planta
|January 16, 2014
Summary
Red light exposure causes rapid electrical changes in oat coleoptile cells, including membrane depolarization and increased cellular coupling. These findings suggest phytochrome
Area of Science:
- Plant Physiology
- Photobiology
- Cellular Electrophysiology
Background:
- Phytochrome mediates plant responses to light.
- Early light responses involve rapid cellular changes.
- Oat coleoptile parenchyma cells are a model system for studying light perception.
Purpose of the Study:
- To investigate the electrical responses of oat coleoptile parenchyma cells to red light.
- To determine the effect of red light on membrane potential and cellular coupling.
- To explore the role of phytochrome in early light responses.
Main Methods:
- Microelectrode recordings of membrane potential.
- Application of current pulses to assess cellular coupling.
- Exposure to red and far-red light stimuli.
Main Results:
- Red light induced a rapid 5-10 mV depolarization of cell membrane potential.
- Repolarization occurred more slowly upon exposure to far-red light.
- Cellular coupling along the longitudinal axis increased approximately twofold, while lateral coupling remained unaffected.
Conclusions:
- Rapid membrane potential changes support a membrane-localized site for early phytochrome action.
- Increased longitudinal cellular coupling suggests phytochrome may influence plasmodesmata.
- These findings provide insights into the biophysical mechanisms underlying photomorphogenesis.
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