A cyclic peptide toolkit reveals mechanistic principles of peptidylarginine deiminase IV regulation
Peptidylarginine deiminase IV (PADI4, PAD4) deregulation promotes the development of autoimmunity, cancer, atherosclerosis and age-related tissue fibrosis. PADI4 additionally mediates immune responses and cellular reprogramming, although the full extent of its physiological roles is unexplored. Despite detailed molecular knowledge of PADI4 activation in vitro, we lack understanding of its regulation within cells, largely due to a lack of appropriate systems and tools. Here, we develop and apply a set of potent and selective PADI4 modulators. Using the mRNA-display-based RaPID system, we screen >10<sup>12</sup> cyclic peptides for high-affinity, conformation-selective binders. We report PADI4_3, a cell-active inhibitor specific for the active conformation of PADI4; PADI4_7, an inert binder, which we functionalise for the isolation and study of cellular PADI4; and PADI4_11, a cell-active PADI4 activator. Structural studies with PADI4_11 reveal an allosteric binding mode that may reflect the mechanism that promotes cellular PADI4 activation. This work contributes to our understanding of PADI4 regulation and provides a toolkit for the study and modulation of PADI4 across (patho)physiological contexts.
Authors
- Simon Walker (ORCID: https://orcid.org/0000-0001-9185-4922)
- Hiroaki Suga (ORCID: https://orcid.org/0000-0002-5298-9186)
- H Assalaarachchi (ORCID: https://orcid.org/0000-0002-6067-0845)
- Venizelos Papayannopoulos (ORCID: https://orcid.org/0000-0002-3741-8190)
- Robert Walmsley (ORCID: https://orcid.org/0000-0003-3510-7214)
- Tessa Swanton (ORCID: https://orcid.org/0000-0003-1776-080X)
- Dhira Joshi (ORCID: https://orcid.org/0000-0001-8660-2528)
- Maria Chasampalioti (ORCID: https://orcid.org/0000-0001-9782-3107)
- Louise J. Walport (ORCID: https://orcid.org/0000-0002-3795-8365)
- D.J. Benton (ORCID: https://orcid.org/0000-0001-6748-9339)
- Iker Valle Aramburu (ORCID: https://orcid.org/0000-0003-2363-4770)
- Thomas Cummings (ORCID: https://orcid.org/0000-0001-5214-9796)
- Stefania Federico (ORCID: https://orcid.org/0000-0003-3120-6098)
- Hanneke Okkenhaug (ORCID: https://orcid.org/0000-0003-0669-4069)
- Lu Yu (ORCID: https://orcid.org/0000-0001-8378-9112)
- Maria A. Christophorou (ORCID: https://orcid.org/0000-0001-5455-7283)
- M. Teresa Bertran (ORCID: https://orcid.org/0000-0002-8336-0903)
- Rocío Mora-Molina (ORCID: https://orcid.org/0000-0001-7256-732X)
- David Oxley
Institutions
- Babraham Institute (GB)
- Western General Hospital (GB)
- The Francis Crick Institute (GB)
- Imperial College London (GB)
- The University of Tokyo (JP)
- University of Edinburgh (GB)
Publication Details
- Journal
- Nature Communications
- Published
- 2024-11-11
- DOI
- https://doi.org/10.1038/s41467-024-53554-1
- Citations
- 15
- Primary Topic
- Protease and Inhibitor Mechanisms
- Type
- article
- Field-Weighted Citation Impact
- 4.28
Funders
- Wellcome
- Cancer Research UK
- Medical Research Council
- Biotechnology and Biological Sciences Research Council