First Author | Behrendt N | Year | 2000 |
Journal | J Biol Chem | Volume | 275 |
Issue | 3 | Pages | 1993-2002 |
PubMed ID | 10636902 | Mgi Jnum | J:60177 |
Mgi Id | MGI:1352942 | Doi | 10.1074/jbc.275.3.1993 |
Citation | Behrendt N, et al. (2000) A urokinase receptor-associated protein with specific collagen binding properties. J Biol Chem 275(3):1993-2002 |
abstractText | The plasminogen activation cascade system, directed by urokinase and the urokinase receptor, plays a key role in extracellular proteolysis during tissue remodeling. To identify molecular interaction partners of these trigger proteins on the cell, we combined covalent protein cross-linking with mass spectrometry based methods for peptide mapping and primary structure analysis of electrophoretically isolated protein conjugates. A specific tri-molecular complex was observed upon addition of pro-urokinase to human U937 cells. This complex included the urokinase receptor, pro-urokinase, and an unknown, high molecular weight urokinase receptor-associated protein. The tryptic peptide mixture derived from a cross-linked complex of pro-urokinase and the latter protein was analyzed by nanoelectrospray tandem mass spectrometric sequencing. This analysis identified the novel protein as the human homologue of a murine membrane-bound lectin with hitherto unknown function. The human cDNA was cloned and sequenced. The protein, designated uPARAP, is a member of the macrophage mannose receptor protein family and contains a putative collagen-binding (fibronectin type II) domain in addition to 8 C-type carbohydrate recognition domains. It proved capable of binding strongly to a single type of collagen, collagen V. This collagen binding reaction at the exact site of plasminogen activation on the cell may lead to adhesive functions as well as a contribution to cellular degradation of collagen matrices. |