Quantification of plant cell coupling with live-cell microscopy.

Area of Science:

• Plant Biology
• Cell Biology
• Biophysics

Background:

• Cell-to-cell transport of nutrients and signaling molecules is vital for plant growth and development.
• Understanding molecular movement across the cell wall interface, particularly through plasmodesmata, is crucial for processes like carbon allocation and pathogen response.
• Plasmodesmata, the channels connecting plant cells, regulate transport based on size exclusion limits and physiological adaptations.

Purpose of the Study:

• To develop a noninvasive method for precisely measuring plasmodesmata-mediated cell wall permeability for small molecules in living plant cells.
• To enable detailed analysis of cell coupling in complex tissues.

Main Methods:

• Utilized photoactivation of caged fluorescein, a non-fluorescent tracer, which is passively taken up by plant tissues.
• Employed confocal microscopy to monitor the spread of activated fluorescein from a target cell to neighboring cells.
• Integrated high-speed acquisition techniques (resonant scanning or spinning disc confocal microscopy) to capture 3D time-series data.

Main Results:

• The photoactivation method provides a high signal-to-noise ratio, enabling precise measurement of tracer movement.
• The technique allows for noninvasive, in vivo determination of cell coupling and plasmodesmata permeability.
• Generated comprehensive 3D time-series data containing functional and anatomical information.

Conclusions:

• The described noninvasive approach accurately quantifies plasmodesmata-mediated cell wall permeability in living plant cells.
• This method offers a powerful tool for studying cell-to-cell communication and transport dynamics in plants.
• Facilitates research into plant growth, development, and responses to environmental stimuli.