The 6TM family of K channels comprises the voltage-gated K_V subfamilies, the EAG subfamily (which includes hERG channels), the Ca²⁺-activated Slo subfamily (actually with 7TM, termed BK) and the Ca²⁺-activated SK subfamily. These channels possess a pore-forming α subunit that comprise tetramers of identical subunits (homomeric) or of different subunits (heteromeric). Heteromeric channels can only be formed within subfamilies (e.g. K_v1.1 with K_v1.2; K_v7.2 with K_v7.3). The pharmacology largely reflects the subunit composition of the functional channel.

K_v7 channels

K_v7.1-K_v7.5 (KCNQ1-5) K⁺ channels are voltage-gated K⁺ channels with major roles in neurons, muscle cells and epithelia where they underlie physiologically important K⁺ currents, such as the neuronal M-current and the cardiac IKs. Genetic deficiencies in all five KCNQ genes result in human excitability disorders, including epilepsy, autism spectrum disorders, cardiac arrhythmias and deafness. Thanks to the recent knowledge of the structure and function of human KCNQ-encoded proteins, these channels are increasingly used as drug targets for treating diseases [1,21,50].

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Subcommittee members: Lily Y. Jan (Chairperson) Howard Hughes Medical Institute Department of Physiology and Biochemistry University of California San Francisco San Francisco CA 94143, USA Bernard Attali Dept of Physiology and Pharmacology 5th Floor, Room 546 Sackler Medical School, Tel Aviv University Tel Aviv 69978 Israel Jeanne Nerbonne Division of Biology and Biomedical Sciences Washington University St. Louis MO 63110, USA Michael C. Sanguinetti Eccles Institute of Human Genetics University of Utah Salt Lake City UT 84101, USA James S. Trimmer (Past contributor) Department of Neurobiology, Physiology and Behavior University of California Davis Davis CA 95616, USA

Other contributors: K. George Chandy Department of Physiology and Biophysics University of California Irvine Irvine CA 92697 USA M. Hunter Giese Department of Physiology and Cellular Biophysics Columbia University New York NY 10032, USA Stephan Grissmer Institute of Applied Physiology Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany George A. Gutman Department of Microbiology and Molecular Genetics University of California Irvine Irvine CA 92697 USA Michel Lazdunski Institut de Pharmacologie Moleculaire et Cellulaire CNRS-Unité Propre de Recherche 411 Valbonne France David Mckinnon Department of Neurobiology and Behavior The State University of New York at Stony Brook Health Sciences Center Stony Brook NY, 11794 USA Luis A. Pardo Max Planck Institute for Experimental Medicine Abt. Molekulare Biologie Neuronaler Signale Gottingen Germany Gail A. Robertson Department of Physiology University of Wisconsin-Madison Madison WI, 53706 USA Bernardo Rudy Department of Physiology, Neuroscience, and Biochemistry New York University School of Medicine New York NY, 10016 USA Walter Stühmer Max Planck Institute for Experimental Medicine Abt. Molekulare Biologie Neuronaler Signale Gottingen Germany Xiaoliang Wang Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing China