CLONING AND CHARACTERIZATION OF A HUMAN TYPE-II RECEPTOR FOR BONE MORPHOGENETIC PROTEINS

Bone morphogenetic proteins (BMPs) are members of the transforming gro wth factor beta superfamily. Several members of this family have been shown to transduce their signals through binding to type I and type II serine(threonine) kinase receptors. Here we report the cDNA cloning a nd characterization of a human type II receptor for BMPs (BMPR-II), wh ich is distantly related to DAF-4 a BMP type II receptor from Caenorha bditis elegans. In transfected COS-1 cells, osteogenic protein (OP)-1/ BMP-7, and. less efficiently BMP-4, bound to BMPR-II. BMPR-II bound li gands only weakly alone, but the binding was facilitated by the presen ce of previously identified type I receptors for BMPs. Binding of OP-1 /BMP-7 to BMPR-II was also observed in nontransfected cell lines. More over, a transcriptional activation signal was transduced by BMPR-II in the presence of type I receptors after stimulation by OP-1/BMP-7.