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Updated: Aug 7, 2026
08:07
A Micropatterning Assay for Measuring Cell Chirality
Published on: March 11, 2022
Cellular asymmetry and individuality in directional sensing
Azadeh Samadani1, Jerome Mettetal, Alexander van Oudenaarden
1Department of Physics and G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Summary
Even in identical conditions, single cells show varied responses to chemical signals due to internal asymmetries. This cellular individuality impacts signal detection but may diversify populations.
Area of Science:
- Cellular Biology
- Biophysics
- Systems Biology
Background:
- Single cells in isogenic populations are often assumed to behave identically in uniform environments.
- However, significant cell-to-cell variability in behavior exists even in genetically identical populations.
Purpose of the Study:
- To investigate variability in gradient-sensing responses of Dictyostelium cells to chemoattractant pulses.
- To understand the impact of cellular asymmetry and individuality on signal detection fidelity.
Main Methods:
- Experimental exposure of Dictyostelium cells to repeated spatiotemporal chemoattractant pulses.
- Observation and quantification of individual cell responses to stimuli.
- Development of a mathematical model integrating cellular asymmetry and extracellular signals.
Main Results:
- Individual cell responses to repeated pulses are reproducible.
- Significant cell-to-cell variability in response direction and magnitude was observed.
- Inherent cellular asymmetries were identified as a key factor in response variability, leading to 'cellular individuality'.
Conclusions:
- Cellular asymmetry and individuality can limit signal detection fidelity.
- This variability may provide a benefit by diversifying phenotypes within isogenic populations.
- A model incorporating intracellular asymmetry successfully predicts population-level responses.
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