Structural Analysis of the Heparin-Binding Site of the NC1 Domain of Collagen XIV by CD and NMR † , ‡ (original) (raw)
Related papers
Structural Analysis of the Heparin-Binding Site of the NC1 Domain of Collagen XIV by CD and NMR,
Biochemistry, 1999
Type XIV collagen, a fibril-associated collagen with interrupted triple helices (FACIT), interacts with the surrounding extracellular matrix and/or with cells via its binding to glycosaminoglycans (GAGs). To further characterize such interactions in the NC1 domain of chicken collagen XIV, we identified amino acids essential for heparin binding by affinity chromatography analysis after proteolytic digestion of the synthetic peptide NC1(84-116). The 3D structure of this peptide was then obtained using circular dichroism and NMR. The NC1(84-116) peptide appeared poorly structured in water, but the stabilization of its conformation by the interaction with hydrophobic surfaces or by using cosolvents (TFE, SDS) revealed a high propensity to adopt an R-helical folding. A 3D structure model of NC1(84-116), calculated from NMR data recorded in a TFE/water mixture, showed that the NC1-heparin binding site forms a amphipathic R-helix exhibiting a twisted basic groove. It is structurally similar to the consensus spatial R-helix model of heparin-binding [Margalit et al. (1993) J. Biol. Chem. 268, 19228-19231], except that the GAG binding domain of NC1 may be extended over 18 residues, that is, the NC1(94-111) segment. In addition, the formation of a hydrophobic groove upon helix formation suggests the contribution of additional sequences to ensure the stability of the GAG-binding domain. Overall the NC1(84-116) model exhibits a nativelike conformation which presents suitably oriented residues for the interaction with a specific GAG.
Mapping the heparin-binding sites on type I collagen monomers and fibrils
The Journal of Cell Biology, 1994
The glycosaminoglycan chains of cell surface heparan sulfate proteoglycans are believed to regulate cell adhesion, proliferation, and extracellular matrix assembly, through their interactions with heparin-binding proteins (for review see Ruoslahti, E. 1988. Annu. Rev. Cell Biol. 4:229-255; and Bernfield, M., R. Kokenyesi, M. Kato, M. T. Hinkes, J. Spring, R. L. Gallo, and E. J. Lose. 1992. Annu. Rev. Cell Biol. 8:365-393). Heparin-binding sites on many extracellular matrix proteins have been described; however, the heparin-binding site on type I collagen, a ubiquitous heparin-binding protein of the extracellular matrix, remains undescribed. Here we used heparin, a structural and functional analogue of heparan sulfate, as a probe to study the nature of the heparan sulfate proteoglycan-binding site on type I collagen. We used affinity coelectrophoresis to study the binding of heparin to various forms of type I collagen, and electron microscopy to visualize the site(s) of interaction o...
Journal of Biological Chemistry, 2006
Collagen type XI is a constituent of the pericellular matrix of chondrocytes and plays a role in the regulation of fibrillogenesis. The amino-terminal domain of collagen type XI α1 chain is a noncollagenous structure that has been identified on the surface of cartilage collagen fibrils. The biochemical composition of the amino-terminal domain varies due to alternative splicing of the primary transcript. Recombinantly expressed α1(XI) amino-terminal domain isoforms were used in this study to investigate potential interactions. Purified products were analyzed for heparan sulfate binding properties. The results demonstrated that two additional binding sites exist within the α1 (XI) amino-terminal domain, one within the amino propeptide and one within the variable region of the amino-terminal domain. Analysis of relative affinities indicated that the site located within the amino propeptide (site 1) was of similar affinity to sites that exist within the major triple helix of collagen type XI. Substitution of amino acid residues 147 to 152 within the amino propeptide by sitedirected mutagenesis resulted in altered affinity for heparan sulfate. The binding site located within the variable region (site 2) demonstrated significantly higher affinity than other sites within the molecule. Displacement of collagen type XI within the pericellular matrix was observed in cell culture in the presence of excess heparan sulfate and by treatment with heparinase. These studies suggest two additional binding sites located within the noncollagenous amino-terminal domain that may play a role in the function of collagen type XI. The localization of collagen type XI within the pericellular matrix may be dependent upon interactions with heparan sulfate proteoglycans, and these are likely to take place in an isoform-specfic manner. Collagens represent an extensive family of proteins that are found in the extracellular matrix. Collagens are assembled from α chains of which there have been reported at least 41 genetically distinct proteins comprising 28 different collagen types (1-3). All collagen family members are modular proteins characterized by regions of triple helix yet differ with respect to the combination and location of the nontriple helical domains present. Collagen type XI, composed of α1, α2, and α3 chains, appears to be concentrated pericellularly and plays a role in the regulation of fibrillogenesis (4,5). The presence of collagen type XI
Protein Science, 1998
Type IV collagen al-a6 chains have important roles in the assembly of basement membranes and are implicated in the pathogenesis of Goodpasture syndrome, an autoimmune disorder, and Alport syndrome, a hereditary renal disease. We report comparative sequence analyses and structural predictions of the noncollagenous C-terminal globular NCl domain (28 sequences). The inferred tree verified that type IV collagen sequences fall into two groups, a1-like and a2-like, and suggested that vertebrate a3/a4 sequences evolved before a l / a 2 and a5/a6. About one fifth of NCl residues were identified to confer either the a 1 or a 2 group-specificity. These residues accumulate opposite charge in subdomain B of a1 (positive) and a 2 (negative) sequences and may play a role in the stoichiometric chain selection upon type IV collagen assembly. Neural network secondary structure prediction on multiple aligned sequences revealed a subdomain core structure consisting of six hydrophobic P-strands and one short a-helix with a significant hydrophobic moment. The existence of opposite charges in the a-helices may carry implications for intersubdomain interactions. The results provide a rationale for defining the epitope that binds Goodpasture autoantibodies and a framework for understanding how certain NC1 mutations may lead to Alport syndrome. A search algorithm, based entirely on amino acid properties, yielded a possible similarity of NCl to tissue inhibitor of metalloproteinases (TIMP) and prompted an investigation of a possible functional relationship. The results indicate that NCl preparations decrease the activity of matrix metalloproteinases 2 and 3 (MMP-2, MMP-3) toward a peptide substrate, though not to [14C]-gelatin. We suggest that an ancestral NC1 may have been incorporated into type IV collagen as an evolutionarily mobile domain carrying proteinase inhibitor function.
Interactions of syndecan-1 and heparin with human collagens
Glycobiology, 1994
Glycosaminoglycan (GAG)-collagen interactions play important roles in cell adhesion and extracellular matrix assembly; however, the chemical bases for these interactions are not fully understood. We have used affinity co-electrophoresis (ACE) (Lee.M.K. and Lander,A.D., Proc. Nad. Acad. Sci. USA, 88, 2768-2772, 1991) to study the binding of the heparan sulphate proteoglycan syndecan-1 and heparin to human collagens. [ 35 S]Syndecan-l [from normal murine mammary gland (NMuMG) epithelial cells] and low-M,. (~6 kDa) [ 125 I]heparin were subjected to electrophoresis through agarose gel lanes containing human collagens at various concentrations, and binding affinities were measured from shifts in migration of the labelled materials. Results demonstrate that the affinities of each collagen for syndecan-1 and low-M r heparin were similar, and followed the order: type V > > type IV = type III * type I > type VI >> type n, and ranged in K^ from ~10~8 to ~3 x 10~6 M. These data suggest that syndecan-1 and heparin may contain similar collagen-binding determinants. It was also found that the same heparin subpopulation was selectively bound with high affinity by each of the collagens. The published amino acid sequences of the six collagens were examined for what are thought to be heparin-binding consensus sequences (Cardin,A.D. and Weintraub,H.J.R., Arteriosclerosis, 9, 21-32, 1989). The presence of such sequences did not correlate with affinity for heparin or syndecan-1, and collagens I, II and III lacked such sequences entirely. The data suggest that collagens may use novel types of binding sites to interact with GAGs.
Proceedings of the National Academy of Sciences, 2012
Fibrillar collagens, the most abundant proteins in the vertebrate body, are involved in a plethora of biological interactions. Plasma protein von Willebrand factor (VWF) mediates adhesion of blood platelets to fibrillar collagen types I, II, and III, which is essential for normal haemostasis. High affinity VWF-binding sequences have been identified in the homotrimeric collagen types II and III, however, it is unclear how VWF recognizes the heterotrimeric collagen type I, the superstructure of which is unknown. Here we present the crystal structure of VWF domain A3 bound to a collagen type III-derived homotrimeric peptide. Our structure reveals that VWF-A3 interacts with all three collagen chains and binds through conformational selection to a sequence that is one triplet longer than was previously appreciated from platelet and VWF binding studies. The VWF-binding site overlaps those of SPARC (also known as osteonectin) and discodin domain receptor 2, but is more extended and shifted toward the collagen amino terminus. The observed collagen-binding mode of VWF-A3 provides direct structural constraints on collagen I chain registry. A VWF-binding site can be generated from the sequences RGQAGVMF, present in the two α1 (I) chains, and RGEOGNIGF, in the unique α2(I) chain, provided that α2(I) is in the middle or trailing position. Combining these data with previous structural data on integrin binding to collagen yields strong support for the trailing position of the α2(I) chain, shedding light on the fundamental and long-standing question of the collagen I chain registry.