title: Identification of a membrane-targeting domain of the transient receptor potential canonical (TRPC)4 channel unrelated to its formation of a tetrameric structure.
abstract: Canonical transient receptor potential (TRPC) channels are Ca(2+)-permeable nonselective cation channels that are activated by a wide variety of stimuli, including G protein-coupled receptors (GPCRs). The TRPC4 channel is expressed in a punctate distribution in the membrane. To identify the regulating region of the channel trafficking to the membrane, we generated deletion mutants of the TRPC4 channel. We determined that when either region that was downstream of the 20 amino acids of the N terminus or the 700-730 amino acids was deleted, the mutants were retained in the endoplasmic reticulum. By coexpression of the wild-type TRPC4 with deletion mutants, we found that the 23-29 amino acids of the N terminus regulate a membrane trafficking. Additionally, by the fluorescence resonance energy transfer (FRET) method, we found that the regions downstream of the 99 amino acid region of the N terminus and upstream of the 730 amino acid region in the C terminus produce assembly of the TRPC4 tetramers. We inferred the candidate proteins that regulate or interact with the 23-29 domain of TRPC4.
authors.affiliation: From the Department of Physiology, Seoul National University College of Medicine.
authors.forename: Jongyun
authors.initials: J
authors.lastname: Myeong
authors.affiliation: From the Department of Physiology, Seoul National University College of Medicine.
authors.forename: Misun
authors.initials: M
authors.lastname: Kwak
authors.affiliation: From the Department of Physiology, Seoul National University College of Medicine.
authors.forename: Chansik
authors.initials: C
authors.lastname: Hong
authors.affiliation: From the Department of Physiology, Seoul National University College of Medicine.
authors.forename: Ju-Hong
authors.initials: JH
authors.lastname: Jeon
authors.affiliation: From the Department of Physiology, Seoul National University College of Medicine insuk@snu.ac.kr.
authors.forename: Insuk
authors.initials: I
authors.lastname: So
mesh_terms: D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism*; D005786:Gene Expression Regulation; D057809:HEK293 Cells; D006801:Humans; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D017384:Sequence Deletion; D050052:TRPC Cation Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
chemical_list: D050052:TRPC Cation Channels; C489571:TRPC4 ion channel
keywords: Fluorescence Resonance Energy Transfer (FRET); Ion Channel; Membrane Trafficking; Phosphatidylinositol; Transient Receptor Potential Channels (TRP Channels)