Disulfide bond reduction and exchange in C4 domain of von Willebrand factor undermines platelet binding

• Verfasst von: Kutzki, Fabian [VerfasserIn]
• Verfasst von: Butera, Diego [VerfasserIn]
• Verfasst von: Lay, Angelina J. [VerfasserIn]
• Verfasst von: Maag, Denis [VerfasserIn]
• Verfasst von: Chiu, Joyce [VerfasserIn]
• Verfasst von: Woon, Heng-Giap [VerfasserIn]
• Verfasst von: Kubař, Tomáš [VerfasserIn]
• Verfasst von: Elstner, Marcus [VerfasserIn]
• Verfasst von: Aponte-Santamaria, Camilo [VerfasserIn]
• Verfasst von: Hogg, Philip J. [VerfasserIn]
• Verfasst von: Gräter, Frauke [VerfasserIn]
• Titel: Disulfide bond reduction and exchange in C4 domain of von Willebrand factor undermines platelet binding
• Verf.angabe: Fabian Kutzki, Diego Butera, Angelina J. Lay, Denis Maag, Joyce Chiu, Heng-Giap Woon, Tomáš Kubař, Marcus Elstner, Camilo Aponte-Santamaría, Philip J. Hogg, Frauke Gräter
• E-Jahr: 2023
• Jahr: August 2023
• Umfang: 12 S.
• Illustrationen: Illustrationen
• Fussnoten: Online verfügbar: 12. April 2023, Artikelversion: 17. Juli 2023 ; Gesehen am 05.10.2023
• Titel Quelle: Enthalten in: Journal of thrombosis and haemostasis
• Ort Quelle: [Amsterdam] : Elsevier, 2003
• Jahr Quelle: 2023
• Band/Heft Quelle: 21(2023), 8 vom: Aug., Seite 2089-2100
• ISSN Quelle: 1538-7836
• DOI: doi:10.1016/j.jtha.2023.03.039
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: biomechanical phenomena
• Sach-SW: blood platelets
• Sach-SW: disulfides
• Sach-SW: integrins
• Sach-SW: protein folding
• K10plus-PPN: 1860772587

Abstract

Background - The von Willebrand factor (VWF) is a key player in regulating hemostasis through adhesion of platelets to sites of vascular injury. It is a large, multi-domain, mechano-sensitive protein that is stabilized by a net of disulfide bridges. Binding to platelet integrin is achieved by the VWF-C4 domain, which exhibits a fixed fold, even under conditions of severe mechanical stress, but only if critical internal disulfide bonds are closed. - Objective - To determine the oxidation state of disulfide bridges in the C4 domain of VWF and implications for VWF’s platelet binding function. - Methods - We combined classical molecular dynamics and quantum mechanical simulations, mass spectrometry, site-directed mutagenesis, and platelet binding assays. - Results - We show that 2 disulfide bonds in the VWF-C4 domain, namely the 2 major force-bearing ones, are partially reduced in human blood. Reduction leads to pronounced conformational changes within C4 that considerably affect the accessibility of the integrin-binding motif, and thereby impair integrin-mediated platelet binding. We also reveal that reduced species in the C4 domain undergo specific thiol/disulfide exchanges with the remaining disulfide bridges, in a process in which mechanical force may increase the proximity of specific reactant cysteines, further trapping C4 in a state of low integrin-binding propensity. We identify a multitude of redox states in all 6 VWF-C domains, suggesting disulfide bond reduction and swapping to be a general theme. - Conclusions - Our data suggests a mechanism in which disulfide bonds dynamically swap cysteine partners and control the interaction of VWF with integrin and potentially other partners, thereby critically influencing its hemostatic function.