The molecular basis of VWF mechano-sensoring: Structure and interactions of VWF domains as the basis for regulation and aggregation

• Applicant: Professorin Dr. Frauke Gräter
• Subject Area: Bioinformatics and Theoretical Biology ; Biophysics
• Term: from 2011 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 172540668

• Final Report Year: 2018

Final Report Abstract

The function of von Willebrand factor, including adhesion and network formation, is tightly regulated by mechanical force, the molecular mechanism of which has remained elusive to a large extent. In this project, we successfully moved forward our understanding on how building blocks of the VWF, domains and domain combinations, perform their function in an atomistic level, in general biochemical terms as well as in shear flow conditions, in health as well as in disease. Most importantly, we have successfully put forward a new mechanism for the force-dependence of the VWF-platelet interaction. In this scenario, which has been validated by experiments within SHENC, VWF A1-GPIb binding is inhibited by a specific A1-A2 interaction, which is relieved by force due to shear flow. In the second funding period, we extended our approach combining molecular modeling and Molecular Dynamics simulations to the dynamics of A1 with binding partners, and of A2 in presence/absence of disease mutants and the vicinal disulfide bond it carries. Secondly, as a major step towards a comprehensive understanding of the force-sensing function of VWF, we obtained structural models and dynamic data under force of the C domains of VWF, most importantly the C4 and C6 domain. We believe these simulations to help to explain on a molecular level the observed increased aggregation of VWF carrying polymorphism in the C4 domain. Finally, we have made progress on developing a Molecular Dynamics scheme, in which disulfide bonds can be reversibly broken and formed, in order to decipher mechanisms of forcedependent disulfide bond shuffling in C-domains (and maybe later D-domains, which carry protein disulfide isomerase motifs). Our work has profoundly contributed to the molecular-level understanding of how collective networks of wild-type and mutant VWF map to clinical presentation.

Publications

• (2014). von Willebrand disease type 2A phenotypes IIC, IID and IIE: A day in the life of shear-stressed mutant von Willebrand factor., Thrombosis and haemostasis 112 : 96-108
  Brehm, M. A.; Huck, V.; Aponte-Santamaría, C.; Obser, T.; Grässle, S.; Oyen, F.; Budde, U.; Schneppenheim, S.; Baldauf, C.; Gräter, F.; Schneider, S. W. and Schneppenheim, R.
  (See online at https://doi.org/10.1160/TH13-11-0902)
• (2014). von Willebrand factor directly interacts with DNA from neutrophil extracellular traps., Arteriosclerosis, thrombosis, and vascular biology 34 : 1382-1389
  Grässle, S.; Huck, V.; Pappelbaum, K. I.; Gorzelanny, C.; Aponte-Santamaría, C.; Baldauf, C.; Gräter, F.; Schneppenheim, R.; Obser, T. and Schneider, S. W.
  (See online at https://doi.org/10.1161/ATVBAHA.113.303016)
• (2015). Forcesensitive autoinhibition of the von Willebrand factor is mediated by interdomain interactions., Biophysical journal 108 : 2312-2321
  Aponte-Santamaría, C.; Huck, V.; Posch, S.; Bronowska, A. K.; Grässle, S.; Brehm, M. A.; Obser, T.; Schneppenheim, R.; Hinterdorfer, P.; Schneider, S. W.; Baldauf, C. and Gräter, F.
  (See online at https://doi.org/10.1016/j.bpj.2015.03.041)
• (2016). Single molecule force spectroscopy data and BD- and MD simulations on the blood protein von Willebrand factor., Data in brief 8 : 1080-1087
  Posch, S.; Aponte-Santamaría, C.; Schwarzl, R.; Karner, A.; Radtke, M.; Gräter, F.; Obser, T.; König, G.; Brehm, M. A.; Gruber, H. J.; Netz, R. R.; Baldauf, C.; Schneppenheim, R.; Tampé, R. and Hinterdorfer, P.
  (See online at https://doi.org/10.1016/j.dib.2016.07.031)
• (2016). von Willebrand factor is dimerized by protein disulfide isomerase., Blood 127 : 1183-1191
  Lippok, S.; Kolšek, K.; Löf, A.; Eggert, D.; Vanderlinden, W.; Müller, J. P.; König, G.; Obser, T.; Röhrs, K.; Schneppenheim, S.; Budde, U.; Baldauf, C.; Aponte-Santamaría, C.; Gräter, F.; Schneppenheim, R.; Rädler, J. O. and Brehm, M. A.
  (See online at https://doi.org/10.1182/blood-2015-04-641902)
• (2017). Accessibility explains preferred thioldisulfide isomerization in a protein domain. Scientific Reports 7, 9858
  Kolšek, K.; Aponte-Santamaría, C.; Gräter F.
  (See online at https://doi.org/10.1038/s41598-017-07501-4)
• (2017). Mutation G1629E Increases von Willebrand Factor Cleavage via a Cooperative Destabilization Mechanism., Biophysical journal 112 : 57-65
  Aponte-Santamaría, C.; Lippok, S.; Mittag, J. J.; Obser, T.; Schneppenheim, R.; Baldauf, C.; Gräter, F.; Budde, U. and Rädler, J. O.
  (See online at https://doi.org/10.1016/j.bpj.2016.11.3202)
• (2017). Mutual A domain interactions in the force sensing protein von Willebrand factor., Journal of structural biology 197 : 57-64
  Posch, S.; Aponte-Santamaría, C.; Schwarzl, R.; Karner, A.; Radtke, M.; Gräter, F.; Obser, T.; König, G.; Brehm, M. A.; Gruber, H. J.; Netz, R. R.; Baldauf, C.; Schneppenheim, R.; Tampé, R. and Hinterdorfer, P.
  (See online at https://doi.org/10.1016/j.jsb.2016.04.012)
• (2018). Autoregulation of von Willebrand factor function by a disulfide bond switch., Science advances 4 : eaaq1477
  Butera, D.; Passam, F.; Ju, L.; Cook, K. M.; Woon, H.; Aponte-Santamaría, C.; Gardiner, E.; Davis, A. K.; Murphy, D. A.; Bronowska, A.; Luken, B. M.; Baldauf, C.; Jackson, S.; Andrews, R.; Gräter, F. and Hogg, P. J.
  (See online at https://doi.org/10.1126/sciadv.aaq1477)