Cloning,expression and purification of human Sox2 gene

To express Sox2 protein,the cDNA was cloned from human ES cells by RT-PCR and constructed into a prokaryotic expression vector to make pET28b-Sox2,which was transformed into Escherichia coli(E.coli) BL21(DE3) cells for expression.IPTG induction of the Sox2 expression was optimized to 0.8 mmol/L for 4 hours at 37℃.Recombinant protein expression was identified by the standard SDS-PAGE and Western blot.The recombinant protein was purified by Ni-NTA affinity chromatography and refolded on column or by dialysis.The final concentration of purified active protein was 0.7 mg/g wet cell weight.