Sci. STKE, 14 November 2006
Biophysics Choosing Channel Selectivity
Katrina L. Kelner
Science, AAAS, Washington, DC 20005, USA
Ion channel proteins form pores in the membranes of cells and are regulated by voltage or small messenger molecules to control information flow to and from cells. The K+ channel, important for the excitability of nerve cells, conducts only K+ ions while completely excluding a smaller ion, Na+. Valiyaveetil et al. show that this selectivity is accomplished in two ways: In the presence of K+, the pore remains open and conductive but collapses when K+ concentrations are low, excluding Na+. In addition, in the conductive state, the pore is lined with multiple binding sites that are specific for K+.
Citation: K. L. Kelner, Choosing Channel Selectivity. Sci. STKE 2006, tw387 (2006).
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