GCN2 Restrains ZAKα-Dependent TNFα Production in LPS+IFNγ Stimulated Macrophages

ABSTRACT: Macrophages orchestrate inflammation through rapid and extensive proteome remodeling, yet the translational programs governing macrophage activation remain poorly defined. Here, we show that inflammatory M(LPS+IFNγ) and reparative M(IL-4) macrophages engage fundamentally distinct translational trajectories. Whereas M(IL-4) macrophages sustain elevated protein synthesis, M(LPS+IFNγ) macrophages undergo a rapid but transient increase in translation that is subsequently restrained by the integrated stress response kinase GCN2. Using puromycin incorporation, polysome profiling, and quantitative proteomics, we demonstrate that GCN2-mediated phosphorylation of eIF2α limits global translation and constrains pro-inflammatory output, particularly TNFα production. Genetic loss of GCN2 results in excessive translation and hyperinflammation driven by the ribosome-associated stress sensor ZAKα. Importantly, pharmacological inhibition of ZAKα in GCN2-deficient macrophages selectively normalizes TNFα secretion, establishing a functional regulatory axis in which GCN2 suppresses ZAKα-dependent inflammatory signaling. Together, these findings redefine translational control as a central checkpoint in macrophage activation, revealing how GCN2 mitigates ribosomal stress to prevent inflammatory hyperactivation, with potential therapeutic implications for TNFα-driven inflammatory diseases.

INSTRUMENT(S):

ORGANISM(S): Mus Musculus (mouse)

SUBMITTER: Barbara Steigenberger  

LAB HEAD: Rodrigo Dias Requião

PROVIDER: PXD075112 | Pride | 2026-09-28

REPOSITORIES: Pride