Tropoelastin binding to fibulins, nidogen-2 and other extracellular matrix proteins.
Elastic fibers in vessel walls and other tissues consist of cross-linked tropoelastin in association with several microfibrillar proteins. In order to understand the molecular basis of these structures, we examined the binding of recombinant human tropoelastin to other extracellular matrix ligands in solid phase binding and surface plasmon resonance assays. These studies demonstrated a particularly high affinity (K(d) about 1 nM) of tropoelastin for microfibrillar fibulin-2 and the recently described nidogen-2 isoform. More moderate affinities were observed for fibulin-1, laminin-1 and perlecan, while several other ligands such as collagens, nidogen-1, fibronectin and BM-40 showed little or no binding. In immunogold staining of mouse aortic media, elastic fibers were heavily decorated with tropoelastin, fibulin-2 and nidogen-2, while the reaction with fibulin-1 was lower. The colocalization of these proteins emphasizes the potential for in vivo interactions.
Sasaki
T
T
Max-Planck-Institut für Biochemie, Am Klopferspitz 18A, D-82152, Martinsried, Germany.
Göhring
W
W
Miosge
N
N
Abrams
W R
WR
Rosenbloom
J
J
Timpl
R
R
D000818:Animals; D001011:Aorta / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D015815:Cell Adhesion Molecules; D004305:Dose-Response Relationship, Drug; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D011485:Protein Binding; D011509:Proteoglycans / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012709:Serum Albumin / Q000378:metabolism; D020349:Surface Plasmon Resonance; D013997:Time Factors; D014333:Tropoelastin / Q000378:metabolism*
D002135:Calcium-Binding Proteins; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D016326:Extracellular Matrix Proteins; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D008562:Membrane Glycoproteins; D011509:Proteoglycans; D011994:Recombinant Proteins; D012709:Serum Albumin; D014333:Tropoelastin; C114729:NID2 protein, human; C060820:fibulin; C071927:perlecan