SEPT5, also known as septin-5, belongs to the septin gene family of nucleotide binding proteins, originally described in yeast as cell division cycle regulatory proteins. Septins are highly conserved in yeast, Drosophila, and mouse and appear to regulate cytoskeletal organization. Disruption of septin function disturbs cytokinesis and results in large multinucleate or polyploid cells. Recombinant human SEPT5 protein, fused to Histag at N-terminus, was expressed in E.coli and purified by using conventional chromatography