4GYX

The von Willebrand Factor A3 domain binding region of type III collagen stabilized by the cysteine knot

Summary for 4GYX

• Entry DOI: 10.2210/pdb4gyx/pdb
• Descriptor: Type III collagen fragment in a host peptide stabilized by the cysteine knot (2 entities in total)
• Functional Keywords: collagen triple helix, type iii collagen cysteine knot, blood clotting, von willebrand factor a3 domain, 4-hydroxylation, extracellular matrix, structural protein
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 3
• Total formula weight: 8625.60

Authors

Boudko, S.P.,Bachinger, H.P. (deposition date: 2012-09-05, release date: 2012-10-17, Last modification date: 2023-09-13)

Primary citation

Boudko, S.P.,Bachinger, H.P.
The NC2 Domain of Type IX Collagen Determines the Chain Register of the Triple Helix.
J.Biol.Chem., 287:44536-44545, 2012

PubMed Abstract: Precise mapping and unraveling the mechanism of interaction or degradation of a certain type of collagen triple helix requires the generation of short and stable collagenous fragments. This is a great challenge especially for hetero-trimeric collagens, where chain composition and register (stagger) are important factors. No system has been reported that can be efficiently used to generate a natural collagenous fragment with exact chain composition and desired chain register. The NC2 domain (only 35-50 residues) of FACIT collagens is a potent trimerization domain. In the case of type IX collagen it provides the efficient selection and hetero-trimerization of three distinct chains. The ability of the NC2 domain to determine the chain register of the triple helix is studied. We generated three possible sequence combinations (α1α1α2, α1α2α1, α2α1α1) of a type I collagen fragment (the binding region for the von Willebrand factor A3 domain) attached to the NC2 domain. In addition, two control combinations were produced that constitute homo-trimers of (α1)(3) or (α2)(3). For the hetero-trimeric constructs, α1α1α2 demonstrated a higher melting temperature than the other two. Binding experiments with the von Willebrand factor A3 domain revealed the homo-trimer of (α1)(3) as the strongest binding construct, whereas the homo-trimer of (α2)(3) showed no binding. For hetero-trimers, α1α1α2 was found to be the strongest binding construct. Differences in thermal stability and binding to the A3 domain unambiguously demonstrate that the NC2 domain of type IX collagen determines not only the chain composition but also the chain register of the adjacent triple helix.

PubMed: 23132862
DOI: 10.1074/jbc.M112.417543

Experimental method

X-RAY DIFFRACTION (1.49 Å)