Topotaxis of active Brownian particles

Area of Science:

• Physics
• Biophysics
• Cell Biology

Background:

• Cellular motion is influenced by topographical gradients on micropatterned substrates.
• Topotaxis, or directed cell movement, is observed at subcellular and large scales.
• Large-scale topotaxis occurs in motile cells navigating obstacle arrays with varying spacing.

Purpose of the Study:

• To introduce a model for large-scale topotaxis using active Brownian particles.
• To investigate how topographical gradients affect particle persistence and motion.
• To demonstrate that persistent motion is sufficient for large-scale topotaxis.

Main Methods:

• Development of a toy model based on active Brownian particles.
• Numerical simulations to analyze particle behavior.
• Analytical arguments to support simulation findings.

Main Results:

• Topographical gradients spatially modulate particle persistence.
• Particles exhibit directed motion towards regions of higher persistence.
• Persistent motion is identified as the key driver for large-scale topotaxis.

Conclusions:

• Active Brownian particle models can explain large-scale topotaxis.
• Topographical gradients influence cell-like particle behavior through persistence modulation.
• This work provides a foundation for studying self-propelled particle and cell dynamics.