The TCF3 gene, also called E2A, encodes two basic helix-loop-helix (bHLH) transcription factors, E12 and E47, through alternative splicing. These transcription factors are involved in mediating canonical Wnt signaling, which is very important in a diverse array of cellular functions such as stem cell proliferation, self-renewal, activation, fate determination, differentiation and aging and senescence. They bind beta-catenin and can act as transcriptional activators or repressors for Wnt target genes, and have been shown to regulate specific target genes during CNS development downstream of Wnt signaling. TCF3/Lef complexes are also known to play key roles in controlling cell fate lineages in multipotent skin stem cells.