Lighting up the linear ubiquitin code: a bioluminescent sensor for M1-specific deubiquitinase activity and drug discovery

Abstract

A luciferase-based reporter, N-Rluc-Ub-Ub-C-Rluc, was developed to selectively monitor M1-deubiquitinase activity via catalytic signal amplification. This high-throughput assay identified baicalein and lumacaftor as novel OTULIN inhibitors from an FDA-approved compound library, validated by STD-NMR and cellular assays. The reporter enables drug discovery targeting linear ubiquitin signaling without specialized synthesis.