The voltage-dependent anion channel as a biological transistor: theoretical considerations.
The voltage-dependent anion channel (VDAC) is a porin of the mitochondrial outer membrane with a bell-shaped permeability-voltage characteristic. This porin restricts the flow of negatively charged metabolites at certain non-zero voltages, and thus might regulate their flux across the mitochondrial outer membrane. Here, we have developed a mathematical model illustrating the possibility of interaction between two steady-state fluxes of negatively charged metabolites circulating across the VDAC in a membrane. The fluxes interact by contributing to generation of the membrane electrical potential with subsequent closure of the VDAC. The model predicts that the VDAC might function as a single-molecule biological transistor and amplifier, because according to the obtained calculations a small change in the flux of one pair of different negatively charged metabolites causes a significant modulation of a more powerful flux of another pair of negatively charged metabolites circulating across the same membrane with the VDAC. Such transistor-like behavior of the VDAC in the mitochondrial outer membrane might be an important principle of the cell energy metabolism regulation under some physiological conditions.
Lemeshko
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VV
School of Physics, Department of Science, National University of Colombia, Medellin Branch, Colombia. vvasilie@perseus.unalmed.edu.co
Lemeshko
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SV
D000818:Animals; D002462:Cell Membrane / Q000502:physiology*; D002713:Chlorine / Q000378:metabolism; D003198:Computer Simulation; D006801:Humans; D015640:Ion Channel Gating / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology*; D008928:Mitochondria / Q000502:physiology*; D008954:Models, Biological; D018272:Porins / Q000502:physiology*; D011188:Potassium / Q000378:metabolism; D014173:Transistors, Electronic; D050994:Voltage-Dependent Anion Channels
D018272:Porins; D050994:Voltage-Dependent Anion Channels; D002713:Chlorine; D011188:Potassium