Identification of a key residue mediating bone morphogenetic protein (BMP)-6 resistance to noggin inhibition allows for engineered BMPs with superior agonist activity.
Bone morphogenetic proteins (BMPs) are used clinically to induce new bone formation in spinal fusions and long bone non-union fractures. However, large amounts of BMPs are needed to achieve these effects. BMPs were found to increase the expression of antagonists, which potentially limit their therapeutic efficacy. However, the relative susceptibility of osteoinductive BMPs to different antagonists is not well characterized. Here we show that BMP-6 is more resistant to noggin inhibition and more potent in promoting osteoblast differentiation in vitro and inducing bone regeneration in vivo when compared with its closely related BMP-7 paralog. Noggin was found to play a critical role as a negative feedback regulator of BMP-7 but not BMP-6-induced biological responses. Using BMP-6/7 chimeras, we identified lysine 60 as a key residue conferring noggin resistance within the BMP-6 protein. A remarkable correlation was found between the presence of a lysine at this position and noggin resistance among a panel of osteoinductive BMPs. Introduction of a lysine residue at the corresponding positions of BMP-2 and BMP-7 allowed for molecular engineering of recombinant BMPs with increased resistance to noggin antagonism.
Song
Kening
K
Stryker Biotech, Hopkinton, Massachusetts 01748, USA.
Krause
Carola
C
Shi
Songting
S
Patterson
Marilyn
M
Suto
Robert
R
Grgurevic
Lovorka
L
Vukicevic
Slobodan
S
van Dinther
Maarten
M
Falb
Dean
D
Ten Dijke
Peter
P
Alaoui-Ismaili
Moulay Hicham
MH
D000595:Amino Acid Sequence; D000818:Animals; D055418:Bone Morphogenetic Protein 6 / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D055419:Bone Morphogenetic Protein 7 / Q000235:genetics / Q000494:pharmacology; D001861:Bone Regeneration / Q000502:physiology; D019556:COS Cells; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D002454:Cell Differentiation; D002460:Cell Line; D002522:Chlorocebus aethiops; D025461:Feedback, Physiological; D015870:Gene Expression; D006801:Humans; D008239:Lysine / Q000737:chemistry; D008297:Male; D059630:Mesenchymal Stem Cells / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010006:Osteoblasts / Q000166:cytology; D010012:Osteogenesis / Q000187:drug effects; D015202:Protein Engineering; D054730:Protein Interaction Domains and Motifs; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D000099176:Noggin Protein
D055418:Bone Morphogenetic Protein 6; D055419:Bone Morphogenetic Protein 7; D002352:Carrier Proteins; D008239:Lysine; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D000099176:Noggin Protein; C525816:BMP6 protein, human