title: Glycogen Synthase Kinase 3β-mediated Phosphorylation in the Most C-terminal Region of Protein Interacting with C Kinase 1 (PICK1) Regulates the Binding of PICK1 to Glutamate Receptor Subunit GluA2.
abstract: Protein interacting with C kinase 1 (PICK1) is a synaptic protein interacting with the AMPA receptor subunits GluA2/3. The interaction between GluA2 and PICK1 is required for the removal of GluA2 from the synaptic plasma membrane during long-term depression (LTD). It has been suggested that glycogen synthase kinase 3β (GSK-3β) is activated during LTD, but the relationships between GluA2, PICK1, and GSK-3β are not well understood. In particular, the substrate(s) of GSK-3β have not yet been determined. Here we showed that PICK1 is a substrate of GSK-3β. We found that Ser(339), Ser(342), Ser(412), and Ser(416) of PICK1 were putative GSK-3β-mediated phosphorylation sites. Among these sites, Ser(416) played a crucial role in regulating the interaction between GluA2 and PICK1. We showed that replacing Ser(416) with Ala disrupted the GluA2-PICK1 interaction, whereas substituting Ser(416) with Glu or Asp retained this interaction. However, deletion of Ser(416) did not affect the GluA2-PICK1 interaction, and substitution of Ser(416) with Ala did not alter the PICK1-PICK1 interaction. Using image analysis in COS-7 cells with AcGFP1-fused PICK1, we showed that substitution of Ser(416) with Ala increased the formation of AcGFP1-positive clusters, suggesting an increase in the association of PICK1 with the membrane. This may have resulted in the dissociation of the GluA2-PICK1 complexes. Our results indicated that GSK-3β-mediated phosphorylation of PICK1 at Ser(416) was required for its association with the AMPA receptor subunit. Therefore, the GSK-3β-mediated phosphorylation of PICK1 may be a regulating factor during LTD induction.
authors.affiliation: From the Laboratory for Alzheimer's Disease, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan, the Department of Pharmacology, Faculty of Medicine, Saitama Medical University, 38 Moro-hongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan, and syagi@saitama-med.ac.jp.
authors.forename: Sosuke
authors.initials: S
authors.lastname: Yagishita
authors.affiliation: From the Laboratory for Alzheimer's Disease, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Murayama
authors.affiliation: the Department of Pharmacology, Faculty of Medicine, Saitama Medical University, 38 Moro-hongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan, and.
authors.forename: Tomoe
authors.initials: T
authors.lastname: Ebihara
authors.affiliation: the Department of Pharmacology, Faculty of Medicine, Saitama Medical University, 38 Moro-hongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan, and.
authors.forename: Kei
authors.initials: K
authors.lastname: Maruyama
authors.affiliation: From the Laboratory for Alzheimer's Disease, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan, the Department of Aging Neurobiology, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Obu-shi, Aichi 474-8522, Japan kenneth@ncgg.go.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Takashima
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D003598:Cytoskeletal Proteins; D018698:Glutamic Acid / Q000737:chemistry; D006006:Glycogen Synthase / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D047468:Immunoprecipitation; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D018091:Receptors, AMPA / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000737:chemistry
chemical_list: D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D009687:Nuclear Proteins; C498298:PICK1 protein, rat; D018091:Receptors, AMPA; D018698:Glutamic Acid; D012694:Serine; D006006:Glycogen Synthase; D000071679:Glycogen Synthase Kinase 3 beta; C000605508:Gsk3b protein, rat; D038362:Glycogen Synthase Kinase 3; C104722:glutamate receptor ionotropic, AMPA 2
keywords: Tau protein (Tau); glutamate receptor; glycogen synthase kinase 3 (GSK-3); phosphorylation; protein interacting with C kinase 1; synapse