Fig. 6.

Hypothetical model for PKD2L1 gating mechanisms. Mechanisms of gating for PKD2L1 channels can be described as shown in the schematic. The closed-state of PKD2L1 depicted by the homologous model of PKD2 structure (a) implies the non-conductive state blocked hypothetically by sodium ions (marine dots). PKD2L1 represents the conductive state (b). The polycystin domain remains relatively static (a slightly outward eversion) during the gating process independent of the state. When the channel switches from closed to open in response to voltage or other physiological stimuli, its pore coupled with VSD motions dilates both the lower gate and the upper gate by an iris-like (for S6) and clock-like (for VSD) rotation, respectively