Chemoproteomic Profiling of Itaconation by Bioorthogonal Probes in Inflammatory Macrophages

Itaconate is an anti-inflammatory
metabolite involved in pathogen–macrophage
interactions, but the mechanisms underlying its effect are not fully
understood. Competitive cysteine profiling has been performed to interrogate
itaconate’s reactivity in cell lysates, but methods for analyzing
targets of itaconation directly in living macrophages are still lacking.
In this work, we developed a specific bioorthogonal probe, itaconate–alkyne
(ITalk), for quantitative and site-specific chemoproteomic profiling
of itaconation in inflammatory macrophages. ITalk recapitulates the
anti-inflammatory property of itaconate and enables biochemical evaluation
and proteomic analysis of its direct targets. Our study delineates
the widespread landscape of itaconate substrates, providing a versatile
tool and comprehensive resource for investigating its function.