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Updated: Jul 2, 2026
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Live Imaging and Analysis of Muscle Contractions in Drosophila Embryo
Published on: July 9, 2019
Slow modulation of the contraction patterns in Physarum polycephalum
Raphael Saiseau1,2, Valentin Busson2, Marc Durand2
1Department of Physics, University of Konstanz , Konstanz, Germany.
Journal of the Royal Society, Interface
|June 30, 2026
Summary
Physarum polycephalum, a slime mould, exhibits slow modulations in contractile activity. These coordinated behaviors, driven by a transport-mediated regulator, are key to self-organization in this model organism.
Area of Science:
- Cellular Biology
- Biophysics
- Systems Biology
Background:
- Physarum polycephalum is a model organism for studying self-organization and coordination of cellular activity.
- Contractile activity in P. polycephalum is driven by actomyosin cortex waves, generating cytoplasmic flows.
- Slow modulations in contractile activity, occurring over long timescales, are poorly understood.
Purpose of the Study:
- To investigate the poorly characterized slow modulations of contractile activity in P. polycephalum.
- To understand the mechanisms coordinating cellular activity across large spatial scales.
- To characterize the different modes of slow modulation and their relationship to physical properties.
Main Methods:
- Confining P. polycephalum in annular geometries for long-term recordings.
- Quantifying contractile activity and cytoplasmic flows across the organism.
- Utilizing automatic Fourier-based classification to identify modulation modes.
Main Results:
- Identified correlations between contractile wave direction, amplitude modulation, and vein diameter variations.
- Classified three families of slow modulation modes: fundamental rotating, higher order, and standing modes.
- Fundamental rotating modes dominated and scaled linearly with system size, with periods near integer multiples of an intrinsic timescale.
Conclusions:
- Slow modulations are a significant aspect of P. polycephalum's self-organization.
- Observations support a transport-mediated model where a regulator influences local excitability and mechanics.
- This mechanism coordinates activity across the organism over extended timescales.
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