The TRIM21 protein’s PRY-SPRY domain is crucial in immune response by recognizing and degrading intracellular antibodies, yet small-molecule targeting remains underexplored. Here, the authors use a crystallographic fragment screening to identify 109 fragment binders distributing across five distinct binding sites of TRIM21, improve the activity by a fragment merging approach, and establish a NanoBRET assay to enable functional validation of compounds.
- Yeojin Kim
- Aleksandar Lučić
- Stefan Knapp