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arXiv · 1907.08371

Accuracy of position determination in Ca$^{2+}$ signaling

Vaibhav H. Wasnik·Peter Lipp·Karsten Kruse
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Abstract

A living cell senses its environment and responds to external signals. In this work, we study theoretically, the precision at which cells can determine the position of a spatially localized transient extracellular signal. To this end, we focus on the case, where the stimulus is converted into the release of a small molecule that acts as a second messenger, for example, Ca$^{2+}$, and activates kinases that change the activity of enzymes by phosphorylating them. We analyze the spatial distribution of phosphorylation events using stochastic simulations as well as a mean-field approach. Kinases that need to bind to the cell membrane for getting activated provide more accurate estimates than cytosolic kinases. Our results could explain why the rate of Ca$^{2+}$ detachment from the membrane-binding conventional Protein Kinase C$\alpha$ is larger than its phosphorylation rate.

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Vaibhav H. Wasnik, Peter Lipp, Karsten Kruse. 2019-07-19. Accuracy of position determination in Ca$^{2+}$ signaling. https://doi.org/10.1103/physreve.100.022401

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