Rational design of potent small-molecule SMARCA2/A4 degraders acting via the recruitment of FBXO22
Target-anchored monovalent degraders are more drug-like than their bivalent counterparts, Proteolysis Targeting Chimeras (PROTACs), while offering greater target specificity control than E3 ligase-anchored monovalent degraders, also known as molecular glues. However, their discovery has typically been serendipitous, and the rules governing their identification remain unclear. This study focuses on the intentional discovery of SMARCA2/A4 monovalent degraders using a library based on SMARCA2/A4 bromodomain-binding ligands. Compound G-6599 emerged as a lead candidate, showing exceptional degradation potency and specificity for SMARCA2/A4. Mechanistic studies reveal that G-6599 operates through the ubiquitin-proteasome pathway and the E3 ligase FBXO22. G-6599 promotes ternary complex formation between SMARCA2 and FBXO22 involving covalent conjugation to a cysteine residue on the latter. Unlike other recently identified FBXO22-dependent degraders, it does not require biotransformation. The selective degradation ability of G-6599, along with its unique mechanism, highlights the therapeutic potential of target-anchored monovalent degraders.
Authors
- Brett M. Babin (ORCID: https://orcid.org/0000-0002-4133-6665)
- Elisia Villemure (ORCID: https://orcid.org/0000-0002-0902-5189)
- Caroline L. Gilchrist
- Michael R. Costa (ORCID: https://orcid.org/0000-0002-1011-0292)
- Peter Hsu (ORCID: https://orcid.org/0000-0002-9381-6564)
- Joachim Rudolph (ORCID: https://orcid.org/0000-0002-0806-6106)
- Tommy K. Cheung
- Xiaofen Ye (ORCID: https://orcid.org/0009-0001-4465-1839)
- Alexandra Frommlet (ORCID: https://orcid.org/0000-0003-2219-7361)
- Hanna G. Budayeva (ORCID: https://orcid.org/0000-0001-7236-5664)
- Nicholas Endres (ORCID: https://orcid.org/0009-0005-1086-6048)
- Robert L. Yauch (ORCID: https://orcid.org/0000-0001-9478-6283)
- Ke Sherry Li (ORCID: https://orcid.org/0000-0002-2851-6725)
- Jean‐Philippe Fortin (ORCID: https://orcid.org/0000-0001-9328-3852)
- Benjamin T. Walters (ORCID: https://orcid.org/0000-0001-5400-0696)
- Tom Januario
- Mingshuo Zeng (ORCID: https://orcid.org/0000-0003-1082-1227)
- Noriko Ishisoko
- John S.D. Chan (ORCID: https://orcid.org/0000-0002-7137-454X)
- Aaron Lictao (ORCID: https://orcid.org/0009-0000-3389-6016)
- Joyce Liu (ORCID: https://orcid.org/0009-0008-4667-6555)
- Bridget Hoag
Institutions
- Genedata (Switzerland) (CH)
- Gene Therapy Laboratory (FR)
- Genomic Health (United States) (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-11-03
- DOI
- https://doi.org/10.1038/s41467-025-64669-4
- Citations
- 5
- Primary Topic
- Protein Degradation and Inhibitors
- Type
- article
- Field-Weighted Citation Impact
- 4.03
Funders
- Genentech