Sandbox WWC3: Difference between revisions

This channel conducts sodium at nearly the rate of free diffusion <ref name= "crystal"/>. This pore consists of an outer funnel-like vestibule, a selectivity filter, a central cavity, and an intracellular activation gate <ref name= "crystal"/>. Unlike the K+ channel, the Na+ channel conducts sodium ions that are hydrated with four water molecules <ref name= "crystal"/>. Much like with the gating mechanism, each domain does not contribute equally to the selectivity of the pore <ref name= "struct"/>, but the channel selects for sodium 100x greater than it selects for any other ion <ref name= "struct"/>.  

It is likely that the sodium ion can get much closer to the channel than a larger K+ ion. When the ion reaches this distance, there is a more efficient removal of water and the sodium interacts with the Glu117 side chains. Two side chains interact directly with the sodium ion and two side chains form hydrogen bonds with the water molecules <ref name= "crystal"/>.