Diagram representing the revised annotation of the VWF mature subunit structure. This annotation, derived from electron microscopy analysis, demonstrates that the VWF D assemblies are composed of 4 smaller modules: VWF, 8-cysteine (C8), trypsin-like inhibitor (TIL), and E or fibronectin type 1-like modules (E). The previous B and C domains are now re-annotated as 6 tandem VWF C domains. The electron micrograph image of the D1 assembly shown here is from Zhou et al.9 As indicated, there is growing evidence that VWF interacts with a large number of ligands with a range of biological functions. VWFpp indicates VWF propeptide; OPG, osteoprotegerin; PSGL-1, P-selectin glycoprotein ligand-1; β2GPI, beta2 glycoprotein 1; and TSP1, thrombospondin 1.
