Kanały jonowe jako struktury modelowe

Abstrakt

Eukaryotic ion channels have been studied over the last fifty years and an extensive knowledge has been accumulated on their function. We know little, however, about their molecular structures. Most of the structural information on eukaryotic ion channels currently available results from homology modeling based on the structures of their bacterial homologues. The crystal structures of two prokaryotic potassium channels from S. lividans and M. thermautotrophicum served as good models for determining the molecular principles of gating in potassium channels. The channel from S. lividans provides also the best model of K+ selectivity. Based on the structure of another potassium channel that from Aeropyrum pernix, several models of voltage sensing have been proposed. The two bacterial mechanosensitive channels from E. coli are to date the best-characterized mechanosensitive channel molecules in terms of structure and function and they may provide an excellent model for understanding the general principles of mechanotransduction in biological membranes.