Synchronization of Dictyostelium discoideum adhesion and spreading using electrostatic forces

Area of Science:

• Cell Biology
• Biophysics
• Surface Science

Background:

• Cell spreading is crucial for understanding cell-substrate adhesion.
• Dictyostelium discoideum cells naturally levitate over charged surfaces at low ionic concentrations.
• Synchronizing cell behavior is challenging but essential for precise biological studies.

Purpose of the Study:

• To develop a method for synchronizing cell spreading in Dictyostelium discoideum.
• To investigate the molecular events and cellular response times during initial cell adhesion and spreading.
• To establish electrochemical control as a tool for studying intracellular responses to contact.

Main Methods:

• Utilizing a two-chamber device with a porous membrane to rapidly alter ionic concentration.
• Applying a high potential electric pulse to an Indium Tin Oxide surface to induce cell adhesion.
• Monitoring cell spreading and actin polymerization using LimE(Deltacoil)-GFP imaging.
• Quantifying the timing of actin polymerization spots post-electric pulse.

Main Results:

• Achieved highly synchronized cell spreading, with onsets separated by less than 5 seconds.
• Observed synchronized actin polymerization in a series of spots, starting 8-11 seconds after the electric pulse.
• Demonstrated that synchronized actin polymerization activity persists for approximately 40 seconds.
• Quantified cellular response time for actin polymerization following controlled surface contact.

Conclusions:

• Electrochemical synchronization is an effective method for precisely controlling cell-surface interactions.
• This technique allows for the first time the quantification of cellular response times to contact, specifically for actin polymerization.
• The developed method provides a valuable tool for studying the dynamics of cell adhesion and intracellular signaling pathways.