The Genotoxic Stress Sensor ZBP1 Drives Tau Pathology

Genotoxic stress, which includes DNA damage and the mis-localization of DNA and RNA, is a defining feature of tauopathies, Alzheimer's disease, and several other neurodegenerative disorders. Recent findings indicate that activation of the innate immune system in response to genotoxic stress can drive harmful neuroinflammation, compromise neuronal integrity, and promote neurodegeneration. Multiple innate immune sensors of genotoxic stress have recently been discovered, but the contributions of many of these emerging nucleic acid-sensing pathways in neurodegenerative disease pathogenesis remain largely unexplored. Z-DNA binding protein 1 (ZBP1) is one such recently discovered genotoxic stress sensor that has been shown to incite various forms of cell death as well as proinflammatory cytokine production in response to left-handed Z conformations of DNA (Z-DNA) and RNA (Z-RNA). Here, we show that ZBP1 deletion provides protection against tau pathology and neuronal loss in the PS19 mouse model of tauopathy. Moreover, we find that this rescue of tauopathy seen with ZBP1 ablation is associated with dampened activation of microglia and astrocytes. These findings identify ZBP1 as a pivotal genotoxic stress sensor that drives tau pathology, gliosis, and neuronal loss in tauopathy. This work further suggests that targeting ZBP1 may offer a therapeutic strategy to treat tau-mediated neurodegenerative disease.