The role of selectivity filter ion occupancy in voltage gating and inactivation gating in potassium channels
The selectivity filter (SF) has been identified as an important gating structure in many K+ channels and ion permeation can have profound effects on SF gating as e.g. seen for C-type inactivation in Kv and KcsA channels. However, how ion permeation controls SF gating is mechanistically not understood. Our recent findings suggest that K2P channels (e.g. TRAAK) show a particular prominent coupling of ion permeation and SF gating that appears to involve changes in SF ion occupancy depending on voltage and ion species. In this collaborative research proposal MD simulations carried by the de Groot team will be combined with mutagenesis and functional studies to better understand the intimate coupling between ion permeating and SF gating in K2P and Kv channels.