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Structural and biophysical characterization of the type VII collagen vWFA2 subdomain leads to identification of two binding sites.

ABSTRACT: Type VII collagen is an extracellular matrix protein, which is important for skin stability; however, detailed information at the molecular level is scarce. The second vWFA (von Willebrand factor type A) domain of type VII collagen mediates important interactions, and immunization of mice induces skin blistering in certain strains. To understand vWFA2 function and the pathophysiological mechanisms leading to skin blistering, we structurally characterized this domain by X-ray crystallography and NMR spectroscopy. Cell adhesion assays identified two new interactions: one with ?1 integrin via its RGD motif and one with laminin-332. The latter interaction was confirmed by surface plasmon resonance with a KD of about 1 mm. These data show that vWFA2 has additional functions in the extracellular matrix besides interacting with type I collagen.

SUBMITTER: Gebauer JM

PROVIDER: S-EPMC7137805 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Structural and biophysical characterization of the type VII collagen vWFA2 subdomain leads to identification of two binding sites.

Gebauer Jan M JM Flachsenberg Florian F Windler Cordula C Richer Barbara B Baumann Ulrich U Seeger Karsten K

FEBS open bio 20200314 4

Type VII collagen is an extracellular matrix protein, which is important for skin stability; however, detailed information at the molecular level is scarce. The second vWFA (von Willebrand factor type A) domain of type VII collagen mediates important interactions, and immunization of mice induces skin blistering in certain strains. To understand vWFA2 function and the pathophysiological mechanisms leading to skin blistering, we structurally characterized this domain by X-ray crystallography and ...[more]

PMID: 32031736

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