Identification of the Lipid Oxygen Radical Defense pathway and its epigenetic control

Membrane phospholipids are vulnerable to oxidative radicals, and uncontrolled lipid peroxidation affects cell viability. Cells have evolved quality control and defense mechanisms, of which the genetic regulation of is not fully understood. Here, we identify the Lipid Oxygen Radical Defense (LORD) pathway. It is epigenetically repressed, by a complex comprising the KRAB-zinc finger protein ZNF354A, the scaffold protein KAP1/TRIM28, the histone methyltransferase SETDB1, and the transcriptional activator ATF2. Upon lipid peroxide accumulation, p38- and JNK-dependent phosphorylation of ATF2, KAP1, and ZNF354A leads to disassembly of the repressive complex, releasing ZNF354A from specific DNA loci and activating a protective gene network, including NRF2 targets. The pathway thus controls cellular sensitivity to oxidative stress and ferroptosis, revealing a novel layer of epigenetic control in lipid quality control and damage defense. This positions the LORD pathway as a promising therapeutic target for diseases linked to chronic inflammation, neurodegeneration and cancer.