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Biology subjects

Bajusz, D.

Publications and source records attributed to Bajusz, D..

2 recordsLinked to original sources

AI-Assisted Discovery and Optimization of Small Molecule TREM2 Agonists with Functional Microglial Activity

Triggering receptor expressed on myeloid cells 2 (TREM2) is a microglia-specific receptor whose loss-of-function variants increase Alzheimers disease (AD) risk by impairing plaque compaction, survival, and protective microglial programming. While antibody-based agonists have shown promise, their translation is hindered by poor brain penetration and high cost. Here, we report the discovery and optimization of small molecule TREM2 agonists through an AI-assisted virtual screening strategy. Deep Docking of over five million purchasable compounds identified a structurally novel hit, T2K-014, which engaged TREM2 with modest affinity. A SAR-by-catalog campaign led to the identification of T2M-010 as a potent binder. T2M-010 demonstrated favorable in vitro PK properties, including high solubility, passive BBB permeability, moderate metabolic stability, and minimal safety liabilities. Functionally, T2M-010 activated receptor-proximal signaling, inducing SYK phosphorylation in TREM2-expressing cells, and promoted microglial phagocytosis. Together, these findings establish T2M-010 as the most potent small molecule TREM2 binder reported to date capable of driving protective microglial responses relevant to AD.

pharmacology and toxicology↗

Allosteric regulation and crystallographic fragment screening of SARS-CoV-2 NSP15 endoribonuclease

SARS-CoV-2 is the causative agent of COVID-19. The highly conserved viral NSP15 endoribonuclease, NendoU, is a key enzyme involved in viral immune evasion, and a promising target for the development of new classes of antivirals. Yet, the broad variety of recognition sequences, complex assembly and kinetics, and lack of structural complexes hampers the development of new competitive or allosteric inhibitors for this target. Here, we performed enzymatic characterization of NendoU in its monomeric and hexameric form, showing that hexamers are allosteric enzymes with a positive cooperative index of 2. By using cryo-EM at distinct pHs combined with X-ray crystallography and structural analysis, we demonstrate the potential for NendoU to shift between open and closed states, and assembly in larger supramolecular entities, which might serve as a mechanism of self-regulation. Further, we report results from a large fragment screening campaign against NendoU, revealing multiple new allosteric sites for the development of inhibitors.

biochemistry↗