Transcription factor that binds DNA in a sequence-specific manner (By similarity). Participates in the Wnt signaling pathway (By similarity). Activates transcription of target genes in the presence of CTNNB1 and EP300 (By similarity). PIASG antagonizes both Wnt-dependent and Wnt-independent activation by LEF1 (By similarity). TLE1, TLE2, TLE3 and TLE4 repress transactivation mediated by LEF1 and CTNNB1 (By similarity). Regulates T-cell receptor alpha enhancer function (By similarity). Required for IL17A expressing gamma-delta T-cell maturation and development, via binding to regulator loci of BLK to modulate expression (By similarity). May play a role in hair cell differentiation and follicle morphogenesis (By similarity). Binds the armadillo repeat of CTNNB1 and forms a stable complex. Interacts with TLE1, PIASG, ALYREF/THOC4, EP300, MDFI and MDFIC (By similarity). Found in nuclear bodies upon PIASG binding. Proline-rich and acidic regions are implicated in the activation functions of RNA polymerase II transcription factors. Phosphorylated at Thr-153 and/or Ser-164 by NLK. Phosphorylation by NLK at these sites represses LEF1-mediated transcriptional activation of target genes of the canonical Wnt signaling pathway (By similarity). Belongs to the TCF/LEF family.