Mechanism of beta-Catenin and APC-Regulated Transcription at Wnt Target Genes

β-连环蛋白和 APC 调节 Wnt 靶基因转录的机制

• 批准号: 8826040
• 负责人: KATHERINE A JONES
• 金额: $ 45.23万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8826040
• 关键词: APC2 gene; AXIN2 protein; Adenomatous Polyposis Coli; Adenomatous Polyposis Coli Protein; Affinity; Apoptosis; Armadillo Repeat; Binding; Biological Assay; Breast; Cancer Cell Growth; Cell Adhesion; Cell Nucleus; Cells; ChIP-seq; Colon; Colon Carcinoma; Colorectal Cancer; Complex; Coupled; Cues; DNA; DNA Binding; DNA-Binding Proteins; Data; Dissociation; Enhancers; Environment; Enzymes; Felis catus; Fractionation; Future; Gene Expression; Gene Expression Regulation; Gene Targeting; Genes; Genetic Transcription; Genomics; Goals; Health; Human; In Vitro; Kinetics; Length; Link; Malignant Neoplasms; Malignant neoplasm of prostate; Mass Spectrum Analysis; Mediating; Metallothionein; Modeling; Multiprotein Complexes; Mutate; Neoplasm Metastasis; Nuclear; Nuclear Export; Nuclear Extract; PC3 cell line; Phosphorylation; Play; Process; Proteins; Proteomics; Recombinant Proteins; Recruitment Activity; Regulation; Reporting; Repression; Role; Scaffolding Protein; Sedimentation process; Signal Transduction; Sucrose; System; T cell transcription factor 1; TCF7L2 gene; Technology; Testing; Therapeutic; Transactivation; Transcriptional Regulation; Transgenes; Tumor Suppressor Proteins; Zinc; alpha catenin; beta catenin; c-Myc Staining Method; cancer cell; combat; gene repression; genome-wide; human embryonic stem cell; in vivo; inhibitor/antagonist; interest; malignant breast neoplasm; mutant; novel; promoter; prostate cancer cell line; protein function; research study; response; scaffold; tumorigenesis; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): The goal of this project is to understand the mechanism of Wnt/¿-catenin transactivation and its regulation by the adenomatous polyposis coli (APC), a tumor suppressor that is mutated in the majority of human colon cancers. Preliminary data show that the metastatic tumor suppressor ¿-catenin, plays a direct role in the repression of Wnt/¿-catenin-dependent genes through recruitment of the APC tumor suppressor, and repression-coupled exchange of coactivator and corepressor complexes, resulting in release of ¿-catenin from DNA-bound LEF-1. Novel components of APC and ¿-catenin nuclear complexes will be identified by robust and sensitive proteomics analyses and assessed for recruitment to Wnt regulatory loci by genomic ChIP-Seq analysis (Aim 1), the detailed mechanism of APC-mediated repression and coregulator exchange will be defined in HT29-APC colon cancer cells (Aim 2), and the role of ¿-catenin in this process will be studied in prostate and colon cancer cells, as well as in a novel cell-free assay system developed to understand ¿- catenin release from LEF-1. Together, these data will identify new proteins that control Wnt-dependent cancer cell growth and reveal previously unknown roles for the APC and alpha-catenin tumor suppressors in the nucleus.

描述（由申请人提供）：本项目的目标是了解Wnt/<$-连环蛋白反式激活的机制及其由腺瘤性结肠息肉病（APC）（一种在大多数人类结肠癌中突变的肿瘤抑制因子）的调节。初步数据显示，转移性肿瘤抑制因子<$-连环蛋白通过募集APC肿瘤抑制因子，以及共激活因子和共抑制因子复合物的抑制偶联交换，导致<$-连环蛋白从DNA结合的LEF-1中释放，在Wnt/<$-连环蛋白依赖性基因的抑制中发挥直接作用。APC和<$-连环蛋白核复合物的新组分将通过稳健和灵敏的蛋白质组学分析鉴定，并通过基因组ChIP-Seq分析评估其向Wnt调控位点的募集（Aim 1），APC介导的抑制和辅调节因子交换的详细机制将在HT 29-APC结肠癌细胞中定义（Aim 2），以及<$-连环蛋白核复合物的作用。将在前列腺癌和结肠癌细胞中研究β-连环蛋白在这一过程中的作用，以及在一种新的无细胞测定系统中研究β-连环蛋白从LEF-1中的释放。总之，这些数据将确定控制Wnt依赖性癌细胞生长的新蛋白质，并揭示APC和α-连环蛋白肿瘤抑制因子在细胞核中的先前未知作用。