OPG And Function Of The E. Coli Expression System SrtA

Osteoprotegrin(OPG) is a important role of the OPG/RANKL/RANK pathwat in regulation of bone remodeling, immune function, vascular disease and mammary gland development.Recombinant OPG was expressed by baculovirus-infected insect system and eukaryotic expression system. There has been no report so far for the expression of OPG with a prokaryotic expression system.In this study,we have successfully obtained functional OPG by sortase A aided E.coli system.The recombinant OPG could bind to RANKL and TRAIL.The binding affinity of OPG for RANKL and TRAIL was measure by surface plasmon resonance(SPR) and each of KD value is about8.2nM and88.7nM.In addition,the functions of OPG,inhibit osteoclast differentiation and TRAIL-induced apoptosis,were confirmed by osteoclast differentiation assay and apoptosis assay.