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Applications of Spatio-temporal Mapping and Particle Analysis Techniques to Quantify Intracellular Ca2+ Signaling In Situ
Published on: January 7, 2019
How does intracellular Ca2+ oscillate: by chance or by the clock?
Alexander Skupin1, Helmut Kettenmann, Ulrike Winkler
1Department of Theoretical Physics, Hahn Meitner Institut, Berlin, Germany.
Biophysical Journal
|December 11, 2007
Summary
Calcium (Ca2+) oscillations in cells are not deterministic but random spikes. This finding, observed across four cell types, redefines our understanding of cellular signaling dynamics.
Area of Science:
- Cellular Biology
- Biophysics
- Biochemistry
Background:
- Calcium (Ca2+) oscillations are crucial for cellular signaling.
- These oscillations were previously thought to follow deterministic patterns for nearly two decades.
Purpose of the Study:
- To investigate the underlying dynamics of Ca2+ oscillations.
- To determine if Ca2+ oscillations exhibit deterministic or random behavior.
Main Methods:
- Analysis of Ca2+ spike trains in four different cell types.
- Measurement and statistical analysis of interspike intervals (ISIs).
- Utilizing Ca2+ buffers to alter diffusion coefficients and observing effects on oscillations.
Main Results:
- Ca2+ oscillations were characterized as a sequence of random spikes, not deterministic dynamics.
- The standard deviation of ISIs was found to be similar to the average ISI and increased linearly with it.
- Consecutive ISIs were uncorrelated, supporting a random spike model.
- Ca2+ buffering, reducing diffusion, increased ISI average and standard deviation, consistent with random wave nucleation.
Conclusions:
- Ca2+ oscillations are fundamentally stochastic processes, driven by random events like wave nucleation.
- Cellular Ca2+ signaling dynamics are more complex and random than previously modeled.
- Techniques like array-enhanced coherence resonance can induce regularity in these otherwise random oscillations.
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