title: Crystal structure of the PAS domain of the hEAG potassium channel.
abstract: KCNH voltage-gated potassium channels play critical roles in regulating cellular functions. The channel is composed of four subunits, each of which contains six transmembrane helices forming the central pore. The cytoplasmic parts of the subunits present a Per-Arnt-Sim (PAS) domain at the N-terminus and a cyclic nucleotide-binding homology domain at the C-terminus. PAS domains are conserved from prokaryotes to eukaryotes and are involved in sensing signals and cellular responses. To better understand the functional roles of PAS domains in KCNH channels, the structure of this domain from the human ether-à-go-go channel (hEAG channel) was determined. By comparing it with the structures of the Homo sapiens EAG-related gene (hERG) channel and the Drosophila EAG-like K(+) (dELK) channel and analyzing the structural features of the hEAG channel, it was identified that a hydrophobic patch on the β-sheet may mediate interaction between the PAS domain and other regions of the channel to regulate its functions.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, People's Republic of China.
authors.forename: Xue
authors.initials: X
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, People's Republic of China.
authors.forename: Juan
authors.initials: J
authors.lastname: Shao
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Tianjin University, Tianjin 300071, People's Republic of China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Qin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D003001:Cloning, Molecular; D018360:Crystallography, X-Ray; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000737:chemistry / Q000378:metabolism; D000072237:ERG1 Potassium Channel / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D051638:Ether-A-Go-Go Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D010957:Plasmids / Q000737:chemistry* / Q000378:metabolism; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D000072756:Protein Conformation, alpha-Helical; D000072757:Protein Conformation, beta-Strand; D054730:Protein Interaction Domains and Motifs; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D040681:Structural Homology, Protein
chemical_list: D029721:Drosophila Proteins; D000072237:ERG1 Potassium Channel; C555038:Elk protein, Drosophila; D051638:Ether-A-Go-Go Potassium Channels; C496884:KCNH1 protein, human; C000606913:KCNH2 protein, human; D015221:Potassium Channels; D011994:Recombinant Proteins
keywords: KCNH channels; PAS domain; ether-à-go-go channel; hEAG potassium chanels