Ion channel are sensitive to gravity changes

The effects of gravity on alamethicin doped planar lipid bilayers and on reconstituted porins of Escherichia coli outer membrane, respectively, have been investigated in this paper The aim of the study was to find out whether and how gravity influences the highly simplified system: membrane-ion channel, in order to provide a novel approach to the explanation of gravity effects on living systems. This is necessary, as even single cells can react to gravity, changes without having perceptive organelles. The mechanism of this detection is not clear yet. One possibility might be the detection of gravity by the membrane itself or by the interaction of integral membrane proteins with gravity. Here we show for the first time that gravity directly, influences the integral open state probability of native ion channels (porins) incorporated into planar lipid bilayers. Under hypergravity, especially the open state probability of proteins increased, whereas it is decreased in the microgravity, case. The dependency is sigmoidal with the steepest region at 1 to 1.3 g. In the light of these experiments, a general effect of gravity, on ion channels and membranes seems to be reasonable, possibly providing an explanation for several impacts of gravity, on living systems.