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Published on: May 12, 2023
Membrane trafficking and osmotically induced volume changes in guard cells
1Biology Department, Utah State University, Logan, UT 84322-5305, USA.
Journal of Experimental Botany
|November 8, 2006
Summary
Guard cells adjust membrane area during osmotic changes. Inhibitors like wortmannin and cytochalasin D reduce hydraulic conductivity, suggesting aquaporin involvement in membrane trafficking and volume regulation.
Area of Science:
- Plant Cell Biology
- Plant Physiology
- Membrane Trafficking
Background:
- Guard cells dynamically alter plasma membrane surface area in response to osmotic stress.
- Membrane internalization and remobilization are linked to guard cell volume changes.
Purpose of the Study:
- Investigate how guard cells maintain membrane integrity during rapid volume fluctuations.
- Determine the effects of membrane trafficking inhibitors on guard cell responses to osmotic treatments.
Main Methods:
- Utilized confocal microscopy and epidermal peels of Vicia faba guard cells.
- Quantified guard cell volume changes and calculated hydraulic conductivity kinetics.
- Assessed the impact of wortmannin, cytochalasin D, and arabinanase on cell volume and elasticity.
Main Results:
- Wortmannin and cytochalasin D inhibited volume loss during osmotic down-shock.
- Cytochalasin D, but not wortmannin, inhibited volume increase during osmotic up-shock.
- Arabinanase confirmed to inhibit osmotic volume changes; effects not due to cell wall elasticity alterations.
Conclusions:
- Arabinanase, cytochalasin D, and wortmannin likely reduce plasma membrane hydraulic conductivity, potentially by gating aquaporins.
- Aquaporins may play a role in coordinating guard cell volume changes with membrane trafficking processes.
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