title: Identification of blocker binding site in mouse TRESK by molecular modeling and mutational studies.
abstract: TWIK (tandem-pore domain weak inward rectifying K(+))-related spinal cord K(+) channel, TRESK, a member of the tandem-pore domain K(+) channel family, is the most recently cloned K(2P) channel. TRESK is highly expressed in dorsal root ganglion neuron, a pain sensing neuron, which is a target for analgesics. In this study, a reliable 3D structure for transmembrane (TM) region of mouse TRESK (mTRESK) was constructed, and then the reasonable blocker binding mode of the protein was investigated. The 3D structure of the mTRESK built by homology modeling method was validated with recommend value of stereochemical quality. Based on the validated structure, K(+) channel blocker-bound conformation was obtained by molecular docking and 5ns MD simulation with DPPC lipid bilayer. Our docking study provides the plausible binding mode of known blockers with key interacting residues, especially, F156 and F364. Finally, these modeling results were verified by experimental study with mutation from phenylalanine to alanine (F156A, F364A and F156A/F364A) at the TM2 and TM4. This is the first modeling study for TRESK that can provide structural information of the protein including ligand binding information. These results can be useful in structure based drug design for finding new blockers of the TRESK as potential therapeutic target of pain treatment.
authors.affiliation: Gyeongsang National University, Gazha-dong, Jinju, Republic of Korea.
authors.forename: Songmi
authors.initials: S
authors.lastname: Kim
authors.forename: Yuno
authors.initials: Y
authors.lastname: Lee
authors.forename: Hyun-Min
authors.initials: HM
authors.lastname: Tak
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Park
authors.forename: Young-Sik
authors.initials: YS
authors.lastname: Sohn
authors.forename: Swan
authors.initials: S
authors.lastname: Hwang
authors.forename: Jaehee
authors.initials: J
authors.lastname: Han
authors.forename: Dawon
authors.initials: D
authors.lastname: Kang
authors.forename: Keun Woo
authors.initials: KW
authors.lastname: Lee
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000409:Alanine / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D004252:DNA Mutational Analysis; D004594:Electrophysiology / Q000379:methods; D057809:HEK293 Cells; D006801:Humans; D007477:Ions; D008024:Ligands; D008051:Lipid Bilayers / Q000737:chemistry; D051379:Mice; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010649:Phenylalanine / Q000737:chemistry; D015221:Potassium Channels / Q000378:metabolism*; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D014162:Transfection
chemical_list: D015060:1,2-Dipalmitoylphosphatidylcholine; D000409:Alanine; D007477:Ions; D008024:Ligands; D008051:Lipid Bilayers; D010649:Phenylalanine; D015221:Potassium Channels; C486498:Kcnk18 protein, mouse