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arXiv · 2005.08203

Three-dimensional cytoplasmic calcium propagation with boundaries

Han-Yu Jiang·Jun He
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Abstract

Ca$^{2+}$ plays an important role in cell signal transduction. Its intracellular propagation is the most basic process of Ca$^{2+}$ signaling, such as calcium wave and double messenger system. In this work, with both numerical simulation and mean field ansatz, the 3-dimensional probability distribution of Ca$^{2+}$, which is read out by phosphorylation, is studied in two scenarios with boundaries. The coverage of distribution of Ca$^{2+}$ is found at an order of magnitude of $\mu$m, which is consistent with experimental observed calcium spike and wave. Our results suggest that the double messenger system may occur in the ER-PM junction to acquire great efficiency. The buffer effect of kinase is also discussed by calculating the average position of phosphorylations and free Ca$^{2+}$. The results are helpful to understand the mechanism of Ca$^{2+}$ signaling.

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Han-Yu Jiang, Jun He. 2020-05-17. Three-dimensional cytoplasmic calcium propagation with boundaries. https://doi.org/10.1088/1572-9494%2Fabc7af

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