Immunoglobulin Transcription Factor 1 (ITF1)

The TCF3 gene, also called E2A, encodes 2 basic helix-loop-helix (bHLH) transcription factors, E12 and E47, through alternative splicing. E12 and E47 are involved in regulation of immunoglobulin gene expression .Expression of immunoglobulin genes depends on various sequence motifs in their enhancer and promoter regions. One class of such sequences is the E box, which is found in both heavy and light chain enhancers. The kappa-E2 site has been shown to be important for light chain gene transcription. To isolate cDNAs encoding kappa-E2-binding proteins, Murre et al. (1989) screened a cDNA expression library derived from a human B-cell lymphoma cell line (BJAB) with an oligonucleotide containing a trimerized kappa-E2 site. They identified a partial cDNA encoding a protein that they designated E12.