O'Brien, Harrison Edward Rowe; (2021) The structure, dynamics and interactions of the von Willebrand factor C3 domain. Doctoral thesis (Ph.D), UCL (University College London).

Preview

Text Harrison OBrien PhD thesis.pdf - Submitted Version Download (16MB) | Preview

Abstract

Von Willebrand factor (VWF) is a multimeric haemostatic protein comprised of a series of repeat domains. It is responsible for platelet adhesion to the site of vessel injury, binding to collagen exposed by injury and to platelets by glycoprotein Ibα (GPIbα). It also acts as a carrier for coagulation Factor VIII (FVIII), increasing its half-life in circulation and localising activated FVIII to the site of injury. Synthesised primarily in the endothelial cells, VWF multimers are either released constitutively into the bloodstream or ultra-large multimers are stored in the endothelial cell cytoplasm in cylindrical storage granules, Weibel-Palade bodies. The importance of VWF function on maintaining normal haemostasis is demonstrated by the quantitative and qualitative defects exhibited by von Willebrand disease (VWD), the most common inherited bleeding disorder in the world. Type 1 VWD is most common, caused by specific mutations throughout the multimeric protein and characterised by reduced levels of circulating VWF. Of the 6 C-terminal C domains of VWF, C3 contains the most VWD Type 1 causing mutations. Whilst the molecular structures of other domains which comprise the collagen, GpIbα and FVIII binding sites are well characterised, the C domain structures remain largely unsolved. This thesis presents the structure of the VWF C3 domain solved using nuclear magnetic resonance spectroscopy and the effect of specific disulphide bond mutations on the domain structure. The C3 domain is comprised of two distinct subdomains – SD1 and SD2. SD1 is dominated by two β-sheet structures whilst SD2 comprises a single β-sheet structure. Domain stability is maintained by five disulphide bonds, two in each subdomain and the inter-subdomain relationship preserved by a single disulphide bond connecting the two. Mutations of each individual disulphide bond resulted in incomplete folding of the domain, highlighting their importance in maintaining the structural integrity of the C3 domain.

Download activity - last month

Export as CSVXMLJSON

Download activity - last 12 months

Export as XMLCSVJSON

Downloads by country - last 12 months

Export as JSONCSVXML

Archive Staff Only

View Item