title: IQ Motif and SEC7 Domain-containing Protein 3 (IQSEC3) Interacts with Gephyrin to Promote Inhibitory Synapse Formation.
abstract: Gephyrin is a central scaffold protein that mediates development, function, and plasticity of mammalian inhibitory synapses by interacting with various inhibitory synaptic proteins. Here, we show that IQSEC3, a guanine nucleotide exchange factor for ARF6, directly interacts with gephyrin, an interaction that is critical for the inhibitory synapse localization of IQSEC3. Overexpression of IQSEC3 increases inhibitory, but not excitatory, synapse density in a guanine nucleotide exchange factor activity-dependent manner. Conversely, knockdown of IQSEC3 decreases size of gephyrin cluster without altering gephyrin puncta density. Collectively, these data reveal that IQSEC3 acts together with gephyrin to regulate inhibitory synapse development.
authors.affiliation: From the Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea, the Department of Physiology and BK21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Um
authors.affiliation: From the Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Gayoung
authors.initials: G
authors.lastname: Choii
authors.affiliation: the Department of Physiology and BK21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
authors.forename: Dongseok
authors.initials: D
authors.lastname: Park
authors.affiliation: the Department of Physiology and BK21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
authors.forename: Dongwook
authors.initials: D
authors.lastname: Kim
authors.affiliation: From the Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Sangmin
authors.initials: S
authors.lastname: Jeon
authors.affiliation: the Department of Physiology and BK21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
authors.forename: Hyeyeon
authors.initials: H
authors.lastname: Kang
authors.affiliation: the Shinshu University School of Medicine, Matsumoto 390-8621, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Mori
authors.affiliation: the Department of Molecular Biology, University Medicine Göttingen, Göttingen 37075, Germany.
authors.forename: Theofilos
authors.initials: T
authors.lastname: Papadopoulos
authors.affiliation: the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea.
authors.forename: Taesun
authors.initials: T
authors.lastname: Yoo
authors.affiliation: the Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon 305-701, Republic of Korea, and.
authors.forename: Yeunkum
authors.initials: Y
authors.lastname: Lee
authors.affiliation: the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea, the Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon 305-701, Republic of Korea, and.
authors.forename: Eunjoon
authors.initials: E
authors.lastname: Kim
authors.affiliation: the Shinshu University School of Medicine, Matsumoto 390-8621, Japan, PRESTO, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Tabuchi
authors.affiliation: From the Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea, jaewonko@yonsei.ac.kr.
authors.forename: Jaewon
authors.identifier: http://orcid.org/0000-0001-9184-1574
authors.initials: J
authors.lastname: Ko
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D013569:Synapses / Q000235:genetics / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; C073441:gephyrin
keywords: BRAG3; IQSEC3; SynARFGEF; gephyrin; inhibition mechanism; inhibitory synapse; protein-protein interaction; scaffold protein; synapse; γ-aminobutyric acid (GABA)