title: HIC1 attenuates Wnt signaling by recruitment of TCF-4 and beta-catenin to the nuclear bodies.
abstract: The hypermethylated in cancer 1 (HIC1) gene is epigenetically inactivated in cancer, and in addition, the haploinsufficiency of HIC1 is linked to the development of human Miller-Dieker syndrome. HIC1 encodes a zinc-finger transcription factor that acts as a transcriptional repressor. Additionally, the HIC1 protein oligomerizes via the N-terminal BTB/POZ domain and forms discrete nuclear structures known as HIC1 bodies. Here, we provide evidence that HIC1 antagonizes the TCF/beta-catenin-mediated transcription in Wnt-stimulated cells. This appears to be due to the ability of HIC1 to associate with TCF-4 and to recruit TCF-4 and beta-catenin to the HIC1 bodies. As a result of the recruitment, both proteins are prevented from association with the TCF-binding elements of the Wnt-responsive genes. These data indicate that the intracellular amounts of HIC1 protein can modulate the level of the transcriptional stimulation of the genes regulated by canonical Wnt/beta-catenin signaling.
authors.affiliation: Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Valenta
authors.forename: Jan
authors.initials: J
authors.lastname: Lukas
authors.forename: Lenka
authors.initials: L
authors.lastname: Doubravska
authors.forename: Bohumil
authors.initials: B
authors.lastname: Fafilek
authors.forename: Vladimir
authors.initials: V
authors.lastname: Korinek
mesh_terms: D000818:Animals; D060466:Axin Protein; D002467:Cell Nucleus / Q000378:metabolism*; D017077:Culture Media, Conditioned; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D051741:Kruppel-Like Transcription Factors; D051379:Mice; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D034622:RNA Interference; D015398:Signal Transduction / Q000502:physiology*; D051820:TCF Transcription Factors / Q000235:genetics / Q000378:metabolism*; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: C491761:AXIN2 protein, human; D060466:Axin Protein; D017077:Culture Media, Conditioned; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; C499808:HIC1 protein, human; D051741:Kruppel-Like Transcription Factors; D051820:TCF Transcription Factors; C544894:TCF7L2 protein, human; C544895:Tcf7l2 protein, mouse; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors; D051153:Wnt Proteins; D051176:beta Catenin