Royal College of Surgeons in Ireland
Willis-Fox_PAR1_JTH_Invited_Review.pdf (1.61 MB)

Molecular basis of protease-activated receptor 1 signaling diversity

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journal contribution
posted on 2021-07-05, 09:20 authored by Orla Willis Fox, Roger PrestonRoger Preston
Protease-activated receptors (PARs) are a family of highly conserved G protein-coupled receptors (GPCRs) that respond to extracellular proteases via a unique proteolysis-dependent activation mechanism. Protease-activated receptor 1 (PAR1) was the first identified member of the receptor family and plays important roles in hemostasis, inflammation and malignancy. The biology underlying PAR1 signaling by its canonical agonist thrombin is well characterized; however, definition of the mechanistic basis of PAR1 signaling by other proteases, including matrix metalloproteases, activated protein C, plasmin, and activated factors VII and X, remains incompletely understood. In this review, we discuss emerging insights into the molecular bases for “biased” PAR1 signaling, including atypical PAR1 proteolysis, PAR1 heterodimer and coreceptor interactions, PAR1 translocation on the membrane surface, and interactions with different G-proteins and β-arrestins upon receptor activation. Moreover, we consider how these new insights into PAR1 signaling have acted to spur development of novel PAR1-targeted therapeutics that act to inhibit, redirect, or fine-tune PAR1 signaling output to treat cardiovascular and inflammatory disease. Finally, we discuss some of the key unanswered questions relating to PAR1 biology, in particular how differences in PAR1 proteolysis, signaling intermediate coupling, and engagement with coreceptors and GPCRs combine to mediate the diversity of identified PAR1 signaling outputs.


National Children's Research Centre, Grant/Award Number: C/18/3

Science Foundation Ireland, Grant/Award Number: 15/CDA/3499

Technology and Innovation Development, Grant/Award Number: 18/TIDA/6001



This is the peer reviewed version of the following article: Willis Fox O, Preston RJS. Molecular basis of protease-activated receptor 1 signaling diversity. J Thromb Haemost. 2020 18(1):6-16., which has been published in final form at This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.

Published Citation

Willis Fox O, Preston RJS. Molecular basis of protease-activated receptor 1 signaling diversity. J Thromb Haemost. 2020 18(1):6-16.

Publication Date

24 Sep 2019

PubMed ID



  • Irish Centre for Vascular Biology
  • School of Pharmacy and Biomolecular Sciences

Research Area

  • Health Professions Education
  • Vascular Biology




  • Accepted Version (Postprint)