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arXiv · 1705.02529

Reconstructing the gradient source position from steady-state fluxes to small receptors

Uli Dobramysl·David Holcman
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Abstract

Recovering the position of a source from the fluxes of diffusing particles through small receptors allows a biological cell to determine its relative position, spatial localization and guide it to a final target. However, how a source can be recovered from point fluxes remains unclear. Using the Narrow Escape Time approach for an open domain, we compute the diffusion fluxes of Brownian particles generated by a steady-state gradient from a single source through small holes distributed on a surface in two dimensions. {We find that the location of a source can be recovered when there are at least 3 receptors and the source is positioned no further than 10 cell radii away}, but this condition is not necessary in a narrow strip. The present approach provides a computational basis for the first step of direction sensing of a gradient at a single cell level.

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Uli Dobramysl, David Holcman. 2017-05-06. Reconstructing the gradient source position from steady-state fluxes to small receptors. https://arxiv.org/abs/1705.02529

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