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Quantitative analysis of concentration gradient and ionic currents associated with hyphal tip growth in fungi.

L Limozin·B Denet
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Abstract

It has been shown previously that the nutrient gradient generated by a tip growing elongated cell induces an ionic current entering the cell tip and looping back in the extracellular medium [L. Limozin, B. Denet and P. Pelcé, Phys. Rev. Lett. 78, 4881 (1997)]. We apply this mechanism to the case of hyphae of fungi, using realistic cell geometries, symport kinetics, proton pump permeabilities, and buffer concentrations. We show that this mechanism contributes to a noticeable part of the external current intensity, related inner electrical field and pH gradient, in agreement with experimental measurements. This provides a good example in biological cells of interaction between shape and field, a common property of growing nonliving systems, such as crystalline dendrites or electrodeposition.

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BuffersCell DivisionDiffusionElectric ConductivityFeedbackFungiHydrogen-Ion ConcentrationIon TransportIonsKineticsProton PumpsJournal Article

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L Limozin, B Denet. 2000. Quantitative analysis of concentration gradient and ionic currents associated with hyphal tip growth in fungi.. https://doi.org/10.1103/physreve.62.4067

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