Expression and efficient purification of tag-cleaved active recombinant human insulin-like growth factor-II from Escherichia coli

摘要: Insulin-like growth factor-II (IGF2) is a factor for the control of cell proliferation and apoptosis. To explore clinical use human IGF2, an efficient method production large amount active recombinant hIGF2 necessary. Human IGF2 cDNA was cloned into pET32 vector where it under IPTGinducible T7 promoter. High level soluble thioredoxin (Trx)-hIGF2 fusion protein produced at room temperature following IPTG induction, amounting up to 20% total bacterial proteins. The Trx-hIGF2 purified approximate 95% purity using Ni+-NTA affinity chromatography with overall yield 120 mg per liter culture. After cleavage Trx fragment by enterokinase, tag-free (rhIGF2) passage through column again. Biological activity determined its ability support NIH/3T3 cells activate AKT signaling pathways. Our results demonstrate that rhIGF2 can easily be obtained various applications from E. coli procedure described in this report.