title: PCAF acetylates {beta}-catenin and improves its stability.
abstract: beta-Catenin plays an important role in development and tumorigenesis. However, the effect of a key acetyltransferase p300/CBP-associated factor (PCAF) on beta-catenin signaling is largely unknown. In this study, we found PCAF could increase the beta-catenin transcriptional activity, induce its nuclear translocation, and up-regulate its protein level by inhibiting its ubiquitination and improving its stability. Further studies showed that PCAF directly binds to and acetylates beta-catenin. The key ubiquitination sites Lys-19 and Lys-49 of beta-catenin were shown as the critical residues for PCAF-induced acetylation and stabilization. Knockdown of PCAF in colon cancer cells markedly reduced the protein level, transcriptional activity, and acetylation level of beta-catenin; promoted cell differentiation; inhibited cell migration; and repressed xenografted tumorigenesis and tumor growth in nude mice. All these data demonstrate that PCAF acetylates beta-catenin and regulates its stability, and they raise the prospect that therapies targeting PCAF may be of clinical use in beta-catenin-driven diseases, such as colon cancer.
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, Shanghai, China.
authors.forename: Xinjian
authors.initials: X
authors.lastname: Ge
authors.forename: Qihuang
authors.initials: Q
authors.lastname: Jin
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.forename: Tingting
authors.initials: T
authors.lastname: Yan
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Zhai
mesh_terms: D000107:Acetylation; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008239:Lysine / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D055550:Protein Stability; D015398:Signal Transduction / Q000502:physiology*; D015533:Transcriptional Activation; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*; D050880:p300-CBP Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
chemical_list: D008239:Lysine; D051153:Wnt Proteins; D051176:beta Catenin; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor