Non-monotonic fluidization generated by fluctuating edge tensions in confluent tissues.

Area of Science:

• Biophysics
• Cellular mechanics
• Tissue dynamics

Background:

• Multicellular systems display spatial and temporal heterogeneity in biochemical and mechanical properties.
• The impact of spatiotemporally heterogeneous forces on confluent tissue dynamics remains poorly understood.

Purpose of the Study:

• To investigate how fluctuating cell-cell interfacial tensions affect the dynamical and mechanical properties of two-dimensional epithelial monolayers.
• To determine the influence of tension fluctuation amplitude and persistence time on tissue dynamics.

Main Methods:

• Utilized a two-dimensional cellular vertex model.
• Simulated confluent epithelial monolayers with fluctuating cell-cell interfacial tensions.
• Analyzed the effects of varying fluctuation amplitude and persistence time on tissue dynamics.

Main Results:

• The long-time diffusion constant, characterizing cell rearrangements, exhibited a non-monotonic dependence on tension persistence time.
• The diffusion constant increased monotonically with increasing fluctuation amplitude.
• At low and intermediate persistence times, tension fluctuations promoted vertex motion and cell rearrangements.

Conclusions:

• Tension fluctuation dynamics play a crucial role in regulating cell rearrangements within confluent tissues.
• The persistence time of interfacial tension is a critical factor, with non-monotonic effects on tissue rearrangement dynamics.
• Understanding these mechanical heterogeneities is key to comprehending tissue development and homeostasis.