KLF4 is a transcription factor which acts as both an activator and repressor. This protein is expressed principally in erythroid tissues and found predominantly in gut. KLF4 is involved in the differentiation of epithelial cells and may also function in skeletal and kidney development. Recombinant human KLF4 protein, fused to His- CaM-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.