The structure of the lipid-embedded potassium channel voltage sensor determined by double-electron-electron resonance spectroscopy.

ABSTRACT: A four-pulse electron paramagnetic resonance experiment was used to measure long-range inter-subunit distances in reconstituted KvAP, a voltage-dependent potassium (Kv) channel. The measurements have allowed us to reach the following five conclusions about the native structure of the voltage sensor of KvAP. First, the S1 helix of the voltage sensor engages in a helix packing interaction with the pore domain. Second, the crystallographically observed antiparallel helix-turn-helix motif of the voltage-sensing paddle is retained in the membrane-embedded voltage sensor. Third, the paddle is oriented in such a way as to expose one face to the pore domain and the opposite face to the membrane. Fourth, the paddle and the pore domain appear to be separated by a gap that is sufficiently wide for li

SUBMITTER: Vamvouka M 

PROVIDER: S-EPMC2248300 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature