Quantitative Profiling of Protein Carbonylations in Ferroptosis by an Aniline-Derived Probe

Ferroptosis is a regulated form of
necrotic cell death implicated
in carcinogenesis and neurodegeneration that is driven by phospholipid
peroxidation. Lipid-derived electrophiles (LDEs) generated during
this process can covalently modify proteins (“carbonylation”)
and affect their functions. Here we report the development of a quantitative
chemoproteomic method to profile carbonylations in ferroptosis by
an aniline-derived probe. Using the method, we established a global
portrait of protein carbonylations in ferroptosis with >400 endogenously
modified proteins and for the first time, identified >20 residue
sites
with endogenous LDE modifications in ferroptotic cells. Specifically,
we discovered and validated a novel cysteine site of modification
on voltage-dependent anion-selective channel protein 2 (VDAC2) that
might play an important role in sensitizing LDE signals and mediating
ferroptosis. Our results will contribute to the understanding of ferroptotic
signaling and pathogenesis and provide potential biomarkers for ferroptosis
detection.