title: Eradication of pathogenic beta-catenin by Skp1/Cullin/F box ubiquitination machinery.
abstract: The use of Skp1/Cull 1/F box (SCF) ubiquitin-conjugation machinery as a potential knockout tool offers a means of eradicating disease-causing proteins. Here a chimeric F box protein (CFP) was engineered to achieve selective eradication of pathogenic beta-catenin in colorectal cancer. We show that CFP specifically searches for and subsequently links the abnormal beta-catenin to the cellular SCF ubiquitination complex. Introduction of the CFP to colorectal cancer cells induced targeted ubiquitination and proteolytic degradation of nuclear and cytoplasmic free beta-catenin while preserving its normal cellular adhesion counterpart. Elimination of pathogenic beta-catenin suppressed constitutive Wingless/Wnt signaling and inhibited in vitro and in vivo tumor cell growth. This study demonstrates a practical utility of a SCF-based knockout system as a tool in targeting an abnormal protein that affects growth and transformation.
authors.affiliation: Pittsburgh Cancer Institute, and Department of Pathology, University of Pittsburgh, 5117 Centre Avenue, Pittsburgh, PA 15213, USA.
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Su
authors.forename: Shinji
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kojima
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
mesh_terms: D002455:Cell Division / Q000235:genetics*; D002460:Cell Line; D003001:Cloning, Molecular; D015179:Colorectal Neoplasms; D003598:Cytoskeletal Proteins / Q000172:deficiency* / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D015972:Gene Expression Regulation, Neoplastic; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000172:deficiency* / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D025801:Ubiquitin / Q000378:metabolism*; D051176:beta Catenin
chemical_list: C495270:CTNNB1 protein, human; D003598:Cytoskeletal Proteins; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D025801:Ubiquitin; D051176:beta Catenin; D008156:Luciferases; D044843:SKP Cullin F-Box Protein Ligases