title: Structural analysis of the S4-S5 linker of the human KCNQ1 potassium channel.
abstract: KCNQ1 plays important roles in the cardiac action potential and consists of an N-terminal domain, a voltage-sensor domain, a pore domain and a C-terminal domain. KCNQ1 is a voltage-gated potassium channel and its channel activity is regulated by membrane potentials. The linker between transmembrane helices 4 and 5 (S4-S5 linker) is important for transferring the conformational changes from the voltage-sensor domain to the pore domain. In this study, the structure of the S4-S5 linker of KCNQ1 was investigated by solution NMR, circular dichroism and fluorescence spectroscopic studies. The S4-S5 linker adopted a helical structure in detergent micelles. The W248 may interact with the cell membrane.
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), Singapore 138669, Singapore.
authors.forename: Shovanlal
authors.initials: S
authors.lastname: Gayen
authors.affiliation: Institute of Chemical & Engineering Sciences, Agency for Science, Technology and Research (A(∗)STAR), Singapore, Singapore.
authors.forename: Qingxin
authors.initials: Q
authors.lastname: Li
authors.affiliation: Experimental Therapeutics Centre, Agency for Science, Technology and Research (A(∗)STAR), Singapore 138669, Singapore. Electronic address: cbkang@etc.a-star.edu.sg.
authors.forename: CongBao
authors.initials: C
authors.lastname: Kang
mesh_terms: D000200:Action Potentials; D002462:Cell Membrane / Q000378:metabolism; D002942:Circular Dichroism; D003902:Detergents / Q000737:chemistry; D006801:Humans; D015640:Ion Channel Gating; D051657:KCNQ1 Potassium Channel / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008564:Membrane Potentials; D008823:Micelles; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D013050:Spectrometry, Fluorescence
chemical_list: D003902:Detergents; D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human; D008823:Micelles
keywords: KCNQ1; Micelles; NMR; Potassium channel; Protein structure