POLE3 is a histone-fold protein that interacts with other histone-fold proteins to bind DNA in a sequence-independent manner. These histone-fold protein dimers combine within larger enzymatic complexes for DNA transcription, replication, and packaging. POLE3 has been shown to interact with SMARCA5. Recombinant human POLE3 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.