Drosophila transforming growth factor beta superfamily proteins induce endochondral bone formation in mammals.

Abstract

Both decapentaplegic (dpp) protein and 60A protein have been implicated in pattern formation during Drosophila melanogaster embryogenesis. Within the C-terminal domain, dpp and 60A are similar to human bone morphogenetic protein 2 (75% identity) and human osteogenic protein 1 (70% identity), respectively. Both recombinant human bone morphogenetic protein 2 and recombinant human osteogenic protein 1 have been shown to induce bone formation in vivo and to restore large diaphyseal segmental defects in various animal models. We examined whether the Drosophila proteins, dpp and 60A, have the capacity to induce bone formation in mammals by using the rat subcutaneous bone induction model. Highly purified recombinant dpp and 60A induced the formation of cartilage, bone, and bone marrow in mammals, as determined by histological observations and by measurements of the specific activity of alkaline phosphatase and calcium content of the implants, thereby demonstrating that related proteins from phylogenetically distant species are capable of inducing bone formation in mammals when placed in sites where progenitor cells are available.Embryonic bone development begins with migration of mesenchymal cells to a predetermined site where they either condense, proliferate, and differentiate directly into boneforming cells or pass through an intermediate cartilage stage before they are replaced with bone. In adult life, bone has a remarkable potential to repair itself upon fracture through a process that recapitulates embryonic bone development. Urist (1) and Reddi and Huggins (2) have shown that the cellular events involved in embryonic bone development are reproduced in predictable intervals in subcutaneous implants of demineralized bone matrix in rats. By employing a reconstitution assay in the rat subcutaneous bone induction model (3, 4) and molecular cloning approaches, several osteogenic proteins (OPs), also called bone morphogenetic proteins [BMPs; BMP-2 through BMP-6, OP-1 (also called BMP-7), and OP-2] have been identified (5-8). The predicted amino acid sequences of these proteins indicate that they are all members of the transforming growth factor f8 (TGF-f3) superfamily, sharing a high degree of homology within the C-terminal seven-cysteine domain (9).The TGF-,p superfamily members are signaling molecules thought to be responsible for specific morphogenic events during development (9, 10). For example, increasing concentrations of Xenopus activins can cause animal cap cells to differentiate into various cell types (11) while BMP-4 (closely related to BMP-2) can instruct a ventral posterior positional cell fate on developing mesoderm in the Xenopus blastula (12, 13). In the mouse, localized expression of BMPs has been reported in skin, heart, nervous system, and developing limbs (14). A recent study demonstrates that mutation of BMP-5The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 so...

Human Bone Morphogenetic Protein 2 Contains a Heparin‐Binding Site which Modifies Its Biological Activity

“…BMP-2 is eluted only at high salt (0.7 M NaCI) and in the presence of 6 M urea from a heparin-Sepharose column . A direct physical binding of BMP-2 to heparin at physiological pH and salt concentrations, Celeste et al (1990) and Ozkaynak et al (1992), those of the Drosophila proteins from Sampath et al (1993). The bracketed residue in human BMP-2 is present only in the recombinant protein from E. coli.…”

“…The mature BMP-2 protein is closely related to the Drosophila dpp protein (Padgett et al, 1993) and the Xenopus BMP-2 (Plessow et al, 1991). The human BMP-2 can substitute the Drosophila homologue dpp during dorsalventral patterning, and, vice versa, a recombinant dpp protein induces ectopic bone formation in rats (Padgett et al, 1993;Sampath et al, 1993). BMP-2 and the other BMP have great potential for medical therapeutic applications, in particular beCorrespondence to W. Sebald, Physiologische Chemie 11, TheodorBoveri-Institut fur Biowissenschaften (Biozentrum) der Universitat, Am Hubland, D-97074 Wiirzburg, Germany F a : f 4 9 931 888 4113.…”

Cloning and Characterization of a Novel Member of the Transforming Growth Factor-β/Bone Morphogenetic Protein Family

“…The remarkable conservation of these proteins and their mechanisms of action are illustrated by the ability of Drosophila dpp to initiate endochondral bone formation in mammals and the ability of the mammalian homologues of dpp (the BMPs) to replace dpp function in Drosophila (22,23). In addition, recent work based on phenotypic effects identified upon inactivation of members of this family also illustrates the crucial role for these proteins in tissue differentiation and interaction in organisms as diverse as Drosophila and humans (Ref.…”

Functional analysis of Bombyx mori Decapentaplegic gene for bone differentiation in a mammalian cell

“…Previous studies have reported that the bone-forming activity of the Drosophila dpp protein can be demonstrated by measuring the specific activity of ALP and the calcium content in subcutaneous rat implants (Sampath et al , 1993). The B. mori dpp gene shares genetic homology with hBMPs and Drosophila dpp.…”

“…The hBMP-4 transgene can rescue dorsal embryonic pattern defects in Drosophila dppmutant flies (Künnapuu and Shimmi, 2010;Padgett et al , 1993). In contrast, Drosophila dpp induces bone formation in mammalian cells (Künnapuu and Shimmi, 2010;Sampath et al , 1993). Moreover, the ligands of BMP-2, BMP-4, and dpp have evolutionarily conserved roles in embryonic development (Künnapuu and Shimmi, 2010).…”