Basic leucine zipper transcriptional factor ATF-like 3, also known as BATF3, is a 127 amino acid protein that localizes to the nucleus and contains one bZIP domain. Interacting with c-Jun, BATF3 functions as a negative regulator of AP-1-mediated transcription, specifically by heterodimerizing with c-Jun and binding to DNA response elements. Recombinant human BATF3 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.