Fibrillin-1 interactions with heparin. Implications for microfibril and elastic fiber assembly.
Fibrillin-1 assembly into microfibrils and elastic fiber formation involves interactions with glycosaminoglycans. We have used BIAcore technology to investigate fibrillin-1 interactions with heparin and with heparin saccharides that are analogous to S-domains of heparan sulfate. We have identified four high affinity heparin-binding sites on fibrillin-1, localized three of these sites, and defined their binding kinetics. Heparin binding to the fibrillin-1 N terminus has particularly rapid kinetics. Hyaluronan and chondroitin sulfate did not interact significantly with fibrillin-1. Heparin saccharides with more than 12 monosaccharide units bound strongly to all four fibrillin-1 sites. Heparin did not inhibit fibrillin-1 N- and C-terminal interactions or RGD-dependent cell attachment, but heparin and MAGP-1 competed for binding to the fibrillin-1 N terminus, and heparin and tropoelastin competed for binding to a central fibrillin-1 sequence. By regulating these key interactions, heparin can profoundly influence microfibril and elastic fiber assembly.
Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom.
Stuart A
SA
Cain
Clair
C
Baldock
John
J
Gallagher
Amanda
A
Morgan
Daniel V
DV
Bax
Anthony S
AS
Weiss
C Adrian
CA
Shuttleworth
Cay M
CM
Kielty
D000818:Animals; D001710:Biotin / Q000737:chemistry; D019921:Biotinylation; D002118:Calcium / Q000378:metabolism; D002240:Carbohydrate Sequence; D003285:Contractile Proteins / Q000737:chemistry; D030562:Databases, Protein; D004492:Edetic Acid / Q000737:chemistry; D005091:Exons; D016326:Extracellular Matrix Proteins / Q000737:chemistry; D000071838:Fibrillin-1; D000071837:Fibrillins; D006025:Glycosaminoglycans / Q000737:chemistry; D006031:Glycosylation; D006493:Heparin / Q000737:chemistry*; D006497:Heparan Sulfate / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D008840:Microfilament Proteins / Q000737:chemistry* / Q000378:metabolism; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009005:Monosaccharides / Q000737:chemistry; D009844:Oligosaccharides / Q000737:chemistry; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D000072260:RNA Splicing Factors; D011994:Recombinant Proteins / Q000737:chemistry; D013552:Swine; D013997:Time Factors; D014333:Tropoelastin / Q000737:chemistry; D054392:Adipokines
D001710:Biotin; D002118:Calcium; D003285:Contractile Proteins; D004492:Edetic Acid; D016326:Extracellular Matrix Proteins; D000071838:Fibrillin-1; D000071837:Fibrillins; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D008840:Microfilament Proteins; D009005:Monosaccharides; D009844:Oligosaccharides; D000072260:RNA Splicing Factors; D011994:Recombinant Proteins; D014333:Tropoelastin; C000605722:FBN1 protein, human; D054392:Adipokines; C016598:microfibrillar protein