title: CK2 accumulation at the axon initial segment depends on sodium channel Nav1.
abstract: Accumulation of voltage-gated sodium channel Nav1 at the axon initial segment (AIS), results from a direct interaction with ankyrin G. This interaction is regulated in vitro by the protein kinase CK2, which is also highly enriched at the AIS. Here, using phosphospecific antibodies and inhibition/depletion approaches, we showed that Nav1 channels are phosphorylated in vivo in their ankyrin-binding motif. Moreover, we observed that CK2 accumulation at the AIS depends on expression of Nav1 channels, with which CK2 forms tight complexes. Thus, the CK2-Nav1 interaction is likely to initiate an important regulatory mechanism to finely control Nav1 phosphorylation and, consequently, neuronal excitability.
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France.
authors.forename: Y E
authors.initials: YE
authors.lastname: Hien
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France.
authors.forename: A
authors.initials: A
authors.lastname: Montersino
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France.
authors.forename: F
authors.initials: F
authors.lastname: Castets
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France.
authors.forename: C
authors.initials: C
authors.lastname: Leterrier
authors.affiliation: INSERM U1036, CEA Grenoble, Institut de Recherches en Technologies et Sciences pour le Vivant, Biologie du Cancer et de l'Infection, Grenoble, France.
authors.forename: O
authors.initials: O
authors.lastname: Filhol
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France. Electronic address: helene.vacher@univ-amu.fr.
authors.forename: H
authors.initials: H
authors.lastname: Vacher
authors.affiliation: Aix-Marseille Université, CNRS, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille-UMR 7286, Marseille, France.
authors.forename: B
authors.initials: B
authors.lastname: Dargent
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D001369:Axons / Q000201:enzymology*; D047390:Casein Kinase II / Q000378:metabolism*; D002478:Cells, Cultured; D015870:Gene Expression; D006624:Hippocampus / Q000166:cytology; D062551:NAV1.2 Voltage-Gated Sodium Channel / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D051381:Rats; D017208:Rats, Wistar
chemical_list: D062551:NAV1.2 Voltage-Gated Sodium Channel; D047390:Casein Kinase II
keywords: Axon initial segment; Dominant negative; Nav1; Phosphorylation; Phosphospecific antibody; Protein kinase CK2