Transcription factor that binds DNA in a sequence-specific manner (By similarity). Participates in the Wnt signaling pathway (PubMed:11445543). Activates transcription of target genes in the presence of CTNNB1 and EP300 (PubMed:12446687). PIASG antagonizes both Wnt-dependent and Wnt-independent activation by LEF1 (PubMed:11731474). 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 (PubMed:23562159). May play a role in hair cell differentiation and follicle morphogenesis (PubMed:11445543). Binds the armadillo repeat of CTNNB1 and forms a stable complex. Binds TLE1, ALYREF/THOC4, MDFI and MDFIC (By similarity). Interacts with NLK (By similarity). Interacts with EP300 and PIASG. Found in nuclear bodies upon PIASG binding. Expressed in Vgamma1.1 and Vgamma2 gamma-delta T-cells, however not expressed in gamma-delta thymocytes fated for Il17a expression (at protein level) (PubMed:17218525, PubMed:23562159). Expressed in alpha-beta T-cell lineages (PubMed:17218525). Expressed in the thymus (PubMed:1827423). Found in distinct epithelial cell compartments of the skin and is abundant in the hair-producing progenitors of the follicle (PubMed:10498690). Detected throughout the basal layer, in ectodermal placodes and the underlying dermal condensates in embryonic skin, and in epithelium and mesenchyme from early hair germs. At birth expression decreases in the basal level of the epidermis and increases in hair bulbs, in particular in matrix and precortex. At day 6-9 expression is concentrated in follicle bulbs and in the hair shaft in a concentric ring of hair-keratin-expressing cells derived from the precortex. Detected in dermal papilla throughout the hair cycle, and in a subset of cells emanating from the bulge to form the secondary hair germ. 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.