Discovery of RGS2-FBXO44 interaction inhibitors using a cell-based NanoBit assay

• DOI: 10.1016/j.molpha.2025.100030
• Publication Date: 2025-03-19T21:06:49Z
• Authors: Sadikshya Aryal; Cindy Shi Yee Wong; Harrison J. McNabb; Ahmad Junaid; Ryan A. Altman; Benita Sjögren
• Keywords: RGS2

Regulators of G protein signaling (RGS) proteins negatively regulate through protein-coupled receptors, and reduced RGS function is involved in numerous pathologies. However, therapeutic intervention challenging, as lack druggable binding pockets enzymatic activity. Instead, targeting mechanisms that control expression show promise an alternative. Pharmacological stabilization RGS2 would be a feasible strategy pathologies associated with levels, such hypertension, heart failure, asthma. rapidly degraded the ubiquitin-proteasomal system, we recently identified E3 ligase recognizes RGS2. F-box Only Protein 44 (FBXO44) acts substrate recognition site for this complex, hypothesize inhibiting RGS2-FBXO44 interaction will lead to enhanced levels. Here, developed NanoLuc Binary Technology (NanoBiT) assay detects between FBXO44. This was used screen 1600 compounds from Life Chemicals protein-protein fragment library. We promising hit, denoted compound 10, inhibits potency 19.6 μM, direct The resulting increase levels dependent on FBXO44, siRNA-mediated FBXO44 knockdown attenuates effect 10. Altogether, 10 represents first example small-molecule inhibitor step toward development molecular probes defined mechanism stabilize SIGNIFICANCE STATEMENT: study provides identify molecules selectively inhibit degradation well ability component proof concept Future action clinically useful low including