BMP Binding Endothelial Regulator (BMPER)

BMPER contains a 39-amino acid signal peptide at the N terminus, 5 tandem cysteine-rich von Willebrand C (VWC)-like domains, 1 von Willebrand D domain, and a C-terminal trypsin inhibitor domain. Expression of recombinant Bmper showed the presence of full-length protein and a 42-kD C-terminal proteolytic fragment. In adult mice, expression of Bmper was high in heart, lung, and skin and low in brain. In situ hybridization of mouse tissue showed dynamic expression of Bmper during embryonic development. At embryonic day 9.5, Bmper staining was seen in the lamina reuniens adjacent to the telencephalic vesicle and in migrating branchial arch cells. At embryonic day 10.5, staining was seen in endothelial cells around the dorsal aorta and in adjacent migrating or mesenchymal cells.