TCF4, also known as immunoglobulin transcription factor 2 and transcription factor 4, is a protein acting as a transcription factor. This protein recognizes an Ephrussi-box ('E-box') binding site ('CANNTG') - a motif first identified in immunoglobulin enhancers. It is expressed predominantly in pre-B-cells, although it is found in other tissues as well. Recombinant human TCF4 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography.