title: Xenopus paraxial protocadherin inhibits Wnt/β-catenin signalling via casein kinase 2β.
abstract: Xenopus paraxial protocadherin (PAPC) regulates cadherin-mediated cell adhesion and promotes the planar cell polarity (PCP) pathway. Here we report that PAPC functions in the Xenopus gastrula as an inhibitor of the Wnt/β-catenin pathway. The intracellular domain of PAPC interacts with casein kinase 2 beta (CK2β), which is part of the CK2 holoenzyme. The CK2α/β complex stimulates Wnt/β-catenin signalling, and the physical interaction of CK2β with PAPC antagonizes this activity. By this mechanism, PAPC restricts the expression of Wnt target genes during gastrulation. These experiments identify a novel function of protocadherins as regulators of the Wnt pathway.
authors.affiliation: Institute of Human Genetics, Ruprecht-Karls-Universitaet Heidelberg, Im Neuenheimer Feld 328, Heidelberg 69120, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Kietzmann
authors.forename: Yingqun
authors.initials: Y
authors.lastname: Wang
authors.forename: Dominik
authors.initials: D
authors.lastname: Weber
authors.forename: Herbert
authors.initials: H
authors.lastname: Steinbeisser
mesh_terms: D000818:Animals; D015820:Cadherins / Q000737:chemistry / Q000378:metabolism*; D047390:Casein Kinase II / Q000378:metabolism*; D008954:Models, Biological; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D000091363:Protocadherins; D015854:Up-Regulation; D060449:Wnt Signaling Pathway; D014981:Xenopus / Q000196:embryology / Q000378:metabolism*; D029867:Xenopus Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D015820:Cadherins; C117635:Pcdh8 protein, Xenopus; D000091363:Protocadherins; D029867:Xenopus Proteins; D047390:Casein Kinase II