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以双顺反子表达载体，在大肠杆菌中经ＩＰＴＧ诱导表达了人骨形成蛋白－３羧基端肽段（ｈＢＭＰ－３Ｃ），表达量占菌体总蛋白量的１８．５％．目的蛋白为２５ｋＤ、含ｈＢＭＰ－３Ｃ端２１５个氨基酸残基组成的肽段，包括ｈＢＭＰ－３成熟肽和一部分前肽．表达产物以包涵体的形式存在，用含ＴｒｉｔｏｎＸ－１００的洗涤液和５ｍｏｌ／Ｌ以下脲溶液连续洗涤，可获得较高纯度的重组人骨形成蛋白－３Ｃ端肽．经复性处理成可溶性蛋白，植入小鼠肌肉内，第１４ｄ组织切片显示有软骨细胞和软骨基质形成，第２１ｄ可见成骨细胞和骨基质形成．将ｒｈＢＭＰ－３Ｃ与脱矿去免疫原性异种骨粒复合后作小鼠肌肉植入试验，２１ｄ组织切片上可见硬质骨形成．结果表明：大肠杆菌表达的ｈＢＭＰ－３Ｃ经复性后具有诱骨活性，糖基化并非ＢＭＰ－３活性所必需．
The bcistronic expression vector was used to express human bone morphogenetic protein-3 carboxyl terminal peptide (hBMP-3C) induced by IPTG in E.coli. The expression level of hBMP-3C was 18.5% of the total bacterial protein. The target protein was 25kD and consisted of 215 amino acid residues of hBMP-3C, including the hBMP-3 mature peptide and a part of propeptide. The expression product exists in the form of inclusion bodies, and was washed successively with a washing solution containing Triton X-100 and a urea solution of 5 mol / L or less to obtain a recombinant human bone morphogenetic protein-3 C peptide with higher purity. Refolded to soluble protein, implanted into the muscle of mice, the 14th day tissue sections showed the formation of chondrocytes and cartilage matrix, and the formation of osteoblasts and bone matrix was observed on the 21th day. The rhBMP-3C was combined with the demineralized immunogenic xanthogranules for mouse muscle implantation test, and solid bone formation was observed on the 21st day. The results showed that hBMP-3C expressed by E.coli had osteoinductivity after refolding, and glycosylation was not necessary for BMP-3 activity.