Crystal Structure of a Soluble Form of the Intracellular Chloride Ion Channel CLIC1 (NCC27) at 1.4-Å Resolution Academic Article uri icon


  • CLIC1 (NCC27) is a member of the highly conserved class of chloride ion channels that exists in both soluble and integral membrane forms. Purified CLIC1 can integrate into synthetic lipid bilayers forming a chloride channel with similar properties to those observed in vivo. The structure of the soluble form of CLIC1 has been determined at 1.4-A resolution. The protein is monomeric and structurally homologous to the glutathione S-transferase superfamily, and it has a redox-active site resembling glutaredoxin. The structure of the complex of CLIC1 with glutathione shows that glutathione occupies the redox-active site, which is adjacent to an open, elongated slot lined by basic residues. Integration of CLIC1 into the membrane is likely to require a major structural rearrangement, probably of the N-domain (residues 1-90), with the putative transmembrane helix arising from residues in the vicinity of the redox-active site. The structure indicates that CLIC1 is likely to be controlled by redox-dependent processes.


  • Harrop, Stephen J
  • DeMaere, Matthew Z
  • Fairlie, W Douglas
  • Reztsova, Tamara
  • Valenzuela, Stella M
  • Mazzanti, Michele
  • Tonini, Raffaella
  • Qiu, Min Ru
  • Jankova, Lucy
  • Warton, Kristina
  • Bauskin, Asne R
  • Wu, Wan Man
  • Pankhurst, Susan
  • Campbell, Terence J
  • Breit, Samuel N
  • Curmi, Paul MG

publication date

  • November 30, 2001

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