title: Sustained Wnt/β-catenin signalling causes neuroepithelial aberrations through the accumulation of aPKC at the apical pole.
abstract: β-Catenin mediates the canonical Wnt pathway by stimulating Tcf-dependent transcription and also associates to N-cadherin at the apical complex (AC) of neuroblasts. Here, we show that while β-catenin activity is required to form the AC and to maintain the cell polarity, oncogenic mutations that render stable forms of β-catenin (sβ-catenin) maintain the stemness of neuroblasts, inhibiting their differentiation and provoking aberrant growth. In examining the transcriptional and structural roles of β-catenin, we find that while β-catenin/Tcf transcriptional activity induces atypical protein kinase C (aPKC) expression, an alternative effect of β-catenin restricts aPKC to the apical pole of neuroepithelial cells. In agreement, we show that a constitutively active form of aPKC reproduces the neuroepithelial aberrations induced by β-catenin. Therefore, we conclude that β-catenin controls the cell fate and polarity of the neuroblasts through the expression and localization of aPKC.
authors.affiliation: Instituto de Investigaciones Biomédicas de Barcelona, CSIC-IDIBAPS, Rossellò 161, Barcelona 08036, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Herrera
authors.affiliation: Instituto de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac 20, Barcelona 08028, Spain.
authors.forename: Murielle
authors.initials: M
authors.lastname: Saade
authors.affiliation: Instituto de Investigaciones Biomédicas de Barcelona, CSIC-IDIBAPS, Rossellò 161, Barcelona 08036, Spain.
authors.forename: Anghara
authors.initials: A
authors.lastname: Menendez
authors.affiliation: Instituto de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac 20, Barcelona 08028, Spain.
authors.forename: Elisa
authors.initials: E
authors.lastname: Marti
authors.affiliation: 1] Instituto de Investigaciones Biomédicas de Barcelona, CSIC-IDIBAPS, Rossellò 161, Barcelona 08036, Spain [2] Instituto de Biología Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac 20, Barcelona 08028, Spain.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Pons
mesh_terms: D000818:Animals; D016764:Cell Polarity; D002642:Chick Embryo; D002645:Chickens / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*; D060449:Wnt Signaling Pathway; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*; D000099221:Protein Kinase C zeta
chemical_list: D011493:Protein Kinase C; D051153:Wnt Proteins; D051176:beta Catenin; D000099221:Protein Kinase C zeta