Solution structure and dynamics of a prototypical chordin-like cysteine-rich repeat (von Willebrand Factor type C module) from collagen IIA.
Chordin-like cysteine-rich (CR) repeats (also referred to as von Willebrand factor type C (VWC) modules) have been identified in approximately 200 extracellular matrix proteins. These repeats, named on the basis of amino acid conservation of 10 cysteine residues, have been shown to bind members of the transforming growth factor-beta (TGF-beta) superfamily and are proposed to regulate growth factor signaling. Here we describe the intramolecular disulfide bonding, solution structure, and dynamics of a prototypical chordin-like CR repeat from procollagen IIA (CR(ColIIA)), which has been previously shown to bind TGF-beta1 and bone morphogenetic protein-2. The CR(ColIIA) structure manifests a two sub-domain architecture tethered by a flexible linkage. Initial structures were calculated using RosettaNMR, a de novo prediction method, and final structure calculations were performed using CANDID within CYANA. The N-terminal region contains mainly beta-sheet and the C-terminal region is more irregular with the fold constrained by disulfide bonds. Mobility between the N- and C-terminal sub-domains on a fast timescale was confirmed using NMR relaxation measurements. We speculate that the mobility between the two sub-domains may decrease upon ligand binding. Structure and sequence comparisons have revealed an evolutionary relationship between the N-terminal sub-domain of the CR module and the fibronectin type 1 domain, suggesting that these domains share a common ancestry. Based on the previously reported mapping of fibronectin binding sites for vascular endothelial growth factor to regions containing fibronectin type 1 domains, we discuss the possibility that this structural homology might also have functional relevance.
O'Leary
Joanne M
JM
Division of Structural Biology, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
Hamilton
John M
JM
Deane
Charlotte M
CM
Valeyev
Najl V
NV
Sandell
Linda J
LJ
Downing
A Kristina
AK
D000465:Algorithms; D000595:Amino Acid Sequence; D001665:Binding Sites; D024043:Collagen Type II / Q000737:chemistry*; D003545:Cysteine / Q000737:chemistry*; D055515:Cysteine-Rich Protein 61; D016207:Cytokines / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D019143:Evolution, Molecular; D005109:Extracellular Matrix / Q000378:metabolism; D005136:Eye Proteins; D005353:Fibronectins / Q000737:chemistry; D006023:Glycoproteins / Q000737:chemistry*; D006801:Humans; D017874:Immediate-Early Proteins / Q000737:chemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D040901:Proteomics; D017386:Sequence Homology, Amino Acid; D012984:Software; D016212:Transforming Growth Factor beta / Q000378:metabolism; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
C501848:CCN1 protein, human; C486602:CHRDL1 protein, human; D024043:Collagen Type II; D055515:Cysteine-Rich Protein 61; D016207:Cytokines; D004220:Disulfides; D005136:Eye Proteins; D005353:Fibronectins; D006023:Glycoproteins; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008024:Ligands; D009419:Nerve Tissue Proteins; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A; C054234:chordin; D003545:Cysteine