Fibulin-1 acts as a cofactor for the matrix metalloprotease ADAMTS-1.
ADAMTS-1 is a metalloprotease that has been implicated in the inhibition of angiogenesis and is a mediator of proteolytic cleavage of the hyaluronan binding proteoglycans, aggrecan and versican. In an attempt to further understand the biological function of ADAMTS-1, a yeast two-hybrid screen was performed using the carboxyl-terminal region of ADAMTS-1 as bait. As a result, the extracellular matrix protein fibulin-1 was identified as a potential interacting molecule. Through a series of analyses that included ligand affinity chromatography, co-immunoprecipitation, pulldown assays, and enzyme-linked immunosorbent assay, the ability of these two proteins to interact was substantiated. Additional studies showed that ADAMTS-1 and fibulin-1 colocalized in vivo. Furthermore, fibulin-1 was found to enhance the capacity of ADAMTS-1 to cleave aggrecan, a proteoglycan known to bind to fibulin-1. We confirmed that fibulin-1 was not a proteolytic substrate for ADAMTS-1. Together, these findings indicate that fibulin-1 is a new regulator of ADAMTS-1-mediated proteoglycan proteolysis and thus may play an important role in proteoglycan turnover in tissues where there is overlapping expression.
Lee
Nathan V
NV
Department of Molecular, Cell, and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California 90095, USA.
Rodriguez-Manzaneque
Juan Carlos
JC
Thai
Shelley N-M
SN
Twal
Waleed O
WO
Luque
Alfonso
A
Lyons
Karen M
KM
Argraves
W Scott
WS
Iruela-Arispe
M Luisa
ML
D051722:ADAM Proteins / Q000737:chemistry / Q000502:physiology*; D000071097:ADAMTS1 Protein; D000818:Animals; D015152:Blotting, Northern; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D002384:Catalysis; D002845:Chromatography; D002846:Chromatography, Affinity; D017077:Culture Media, Conditioned / Q000494:pharmacology; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005838:Genotype; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D007668:Kidney / Q000196:embryology; D008024:Ligands; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D008957:Models, Genetic; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011509:Proteoglycans / Q000737:chemistry; D012313:RNA / Q000737:chemistry; D020798:Two-Hybrid System Techniques
D002135:Calcium-Binding Proteins; D017077:Culture Media, Conditioned; D018076:DNA, Complementary; D008024:Ligands; D011509:Proteoglycans; C060820:fibulin; D012313:RNA; D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; C103859:ADAMTS1 protein, human