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Subunit: Two separate complex-associated pools are found in the cytoplasm. The majority is present as component of an E-cadherin/ catenin adhesion complex composed of at least E-cadherin/CDH1 and beta-catenin/CTNNB1, and possibly alpha-catenin/CTNNA1; the complex is located to adherens junctions. The stable association of CTNNA1 is controversial as CTNNA1 was shown not to bind to F-actin when assembled in the complex. Alternatively, the CTNNA1-containing complex may be linked to F-actin by other proteins such as LIMA1. Another cytoplasmic pool is part of a large complex containing AXIN1, AXIN2, APC, CSNK1A1 and GSK3B that promotes phosphorylation on N-terminal Ser and Thr residues and ubiquitination of CTNNB1 via BTRC and its subsequent degradation by the proteasome. Wnt-dependent activation of DVL antagonizes the action of GSK3B. When GSK3B activity is inhibited the complex dissociates, CTNNB1 is dephosphorylated and is no longer targeted for destruction. The stabilized protein translocates to the nucleus, where it binds TCF/LEF-1 family members, TBP, BCL9, BCL9L and possibly also RUVBL1 and CHD8. Binds CTNNBIP and EP300. CTNNB1 forms a ternary complex with LEF1 and EP300 that is disrupted by CTNNBIP1 binding (By similarity). Interacts with TAX1BP3 (via the PDZ domain); this interaction inhibits the transcriptional activity of CTNNB1 (By similarity). Interacts with AJAP1, BAIAP1, CARM1, CTNNA3, CXADR and PCDH11Y. Binds SLC9A3R1. Interacts with GLIS2 and MUC1. Interacts with SLC30A9. Interacts with XIRP1 (By similarity). Interacts directly with AXIN1; the interaction is regulated by CDK2 phosphorylation of AXIN1 (By similarity). Interacts with SCRIB. Interacts with RAPGEF2 (By similarity). Interacts with PTPRU (via the cytoplasmic juxtamembrane domain). Interacts with EMD. Interacts with TNIK and TCF7L2. Interacts with SESTD1 and TRPC4. Interacts with CAV1. Interacts with TRPV4. The TRPV4 and CTNNB1 complex can interact with CDH1. Interacts with VCL (By similarity). Interacts with PTPRJ. Interacts with PKT7 and CDK2. Interacts with FAT1 (via the cytoplasmic domain) (By similarity). Interacts with NANOS1 and NDRG2. Interacts with isoform 1 of NEK2. Interacts with both isoform 1 and isoform 2 of CDK5. Interacts with PTK6. Interacts with SOX7; this interaction may lead to proteasomal degradation of active CTNNB1 and thus inhibition of Wnt/beta-catenin-stimulated transcription. Identified in a complex with HINT1 and MITF. Interacts with FHIT. The CTNNB1 and TCF7L2/TCF4 complex interacts with PML (isoform PML-4). Interacts with FERMT2. Identified in a complex with TCF7L2/TCF4 and FERMT2. May interact with P-cadherin/CDH3 Sequence caution: Sequence=BAB93475.1; Type=Erroneous initiation; Note=Translation N-terminally extended; Selected PDB 3D structures from [IMAGE] and Proteopedia [IMAGE] for CTNNB1 (see all 18): 1G3J (3D) [IMAGE] 1JDH (3D) [IMAGE] 1JPW (3D) [IMAGE] 1LUJ (3D) [IMAGE] 1P22 (3D) [IMAGE] 1QZ7 (3D) [IMAGE]
Tissue specificity: Expressed in several hair follicle cell types: basal and peripheral matrix cells, and cells of the outer and inner root sheaths. Expressed in colon. Present in cortical neurons (at protein level) [IMAGE] Pathway & Disease-focused RT2 Profiler PCR Arrays i
Function: UniProtKB/Swiss-Prot Summary: CTNB1_HUMAN, P35222 Function: Key downstream component of the canonical Wnt signaling pathway. In the absence of Wnt, forms a complex with AXIN1, AXIN2, APC, CSNK1A1 and GSK3B that promotes phosphorylation on N-terminal Ser and Thr residues and ubiquitination of CTNNB1 via BTRC and its subsequent degradation by the proteasome. In the presence of Wnt ligand, CTNNB1 is not ubiquitinated and accumulates in the nucleus, where it acts as a coactivator for transcription factors of the TCF/LEF family, leading to activate Wnt responsive genes. Involved in the regulation of cell adhesion. Acts as a negative regulator of centrosome cohesion. Involved in the CDK2/PTPN6/CTNNB1/CEACAM1 pathway of insulin internalization. Blocks anoikis of malignant kidney and intestinal epithelial cells and promotes their anchorage-independent growth by down-regulating DAPK2. Disrupts PML function and PML-NB formation by inhibiting RANBP2-mediated sumoylation of PML
Similarity: Belongs to the beta-catenin family Contains 12 ARM repeats [IMAGE]
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