Crystal structure and mechanism of a calcium-gated potassium channel

  title={Crystal structure and mechanism of a calcium-gated potassium channel},
  author={Youxing Jiang and Alice Lee and Jiayun Chen and Martine Cadene and Brian T. Chait and Roderick MacKinnon},
Ion channels exhibit two essential biophysical properties; that is, selective ion conduction, and the ability to gate-open in response to an appropriate stimulus. Two general categories of ion channel gating are defined by the initiating stimulus: ligand binding (neurotransmitter- or second-messenger-gated channels) or membrane voltage (voltage-gated channels). Here we present the structural basis of ligand gating in a K+ channel that opens in response to intracellular Ca2+. We have cloned… 

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The architecture of the pore establishes the physical principles underlying selective K+ conduction, which promotes ion conduction by exploiting electrostatic repulsive forces to overcome attractive forces between K+ ions and the selectivity filter.

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