[Research on expression of somatomedin b domain of proteoglycan 4 and recombinant protein aggregation].

Recombinant protein SMB(PRG4) containing two Somatomedin B domains and a small amount of glycosylation of repetitive sequences of proteoglycan 4 was cloned according to PGR4 gene polymorphism. Mature purification process was established and recombinant protein SMB(PRG4), with high-level expression was purified. By using size-exclusion chromatogaraphy and dynamic light scattering, we found that the recombinant protein self-aggregate to dimeric form. Structure prediction and non-reducing electrophoresis revealed that SMB(PRG4), was a non-covalently bonded dimer.