Efficient expression of a heterodimer of bone morphogenetic protein subunits using a baculovirus expression system

Biochem Biophys Res Commun. 1995 Apr 26;209(3):859-66. doi: 10.1006/bbrc.1995.1578.


Recombinant baculoviruses as expression vectors for Xenopus bone morphogenetic protein (xBMP)-2, 4 and 7 were generated. The conditioned medium of insect cells infected with the virus for xBMP-2 or 4 showed strong alkaline phosphatase-inducing activity in a mouse osteoblastic cell line, MC3T3-E1, although a large portion of the activity remained in the infected cells. In contrast, xBMP-7 was preferentially secreted into the medium, but had only weak activity. Conditioned media following simultaneous inoculation with the viruses for xBMP-7 and for xBMP-2 or 4 showed a remarkably increased level of activity. The increased activity was clearly separated from other peaks derived from single infection on a cation-exchange column and was found to arise from the disulfide-linked heterodimer consisting of xBMP-4 and 7 subunits by immunoblot analysis. The heterodimer also augmented osteocalcin production and parathyroid hormone-sensitivity more strongly than the homodimers. These results suggest that our expression system provides a convenient source of heterodimeric BMP with high osteogenic differentiation-inducing activity.

MeSH terms

  • 3T3 Cells
  • Alkaline Phosphatase / analysis
  • Alkaline Phosphatase / metabolism
  • Animals
  • Baculoviridae
  • Base Sequence
  • Biological Assay
  • Bone Morphogenetic Proteins
  • Cell Differentiation / drug effects
  • Cell Line
  • Chromatography, Ion Exchange
  • DNA Primers
  • Electrophoresis, Polyacrylamide Gel
  • Gene Expression
  • Growth Substances / biosynthesis
  • Kinetics
  • Macromolecular Substances
  • Mice
  • Molecular Sequence Data
  • Molecular Weight
  • Osteoblasts / cytology
  • Osteoblasts / drug effects
  • Parathyroid Hormone / pharmacology
  • Polymerase Chain Reaction
  • Protein Biosynthesis*
  • Proteins / isolation & purification
  • Proteins / pharmacology
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / pharmacology
  • Spodoptera
  • Transfection
  • Xenopus


  • Bone Morphogenetic Proteins
  • DNA Primers
  • Growth Substances
  • Macromolecular Substances
  • Parathyroid Hormone
  • Proteins
  • Recombinant Proteins
  • Alkaline Phosphatase