| Background | Alternative products: Two series of isoforms, L and S, are produced by alternative promoter usage. Additional isoforms seem to exist. Function: Transcriptional activator involved in T-cell lymphocyte differentiation. Necessary for the survival of CD4(+) CD8(+) immature thymocytes. Isoforms lacking the N-terminal CTNNB1 binding domain cannot fulfill this role. Binds to the T-lymphocyte-specific enhancer element (5'-WWCAAAG-3') found in the promoter of the CD3E gene. May also act as a feedback transcriptional repressor of CTNNB1 and TCF7L2 target genes. TLE1, TLE2, TLE3, and TLE4 repress transactivation mediated by TCF7 and CTNNB1. Induction: By TCF7L2 and CTNNB1. Sequence caution: Wrong choice of frame. Similarity: Belongs to the TCF/LEF family. Contains one HMG box DNA-binding domain. Subunit: Binds the armadillo repeat of CTNNB1 and forms a stable complex. Interacts with AES, TLE1, TLE2, TLE3, and TLE4. Tissue specificity: Predominantly in T-cells. Also detected in proliferating intestinal epithelial cells and in the basal epithelial cells of the mammary gland epithelium. |
