ZBP1-induced Inflammation and REcognition of Z-Nucleic Acids

ongoing

Nucleic acids are potent inducers of an immune response. Nucleic acids normally exist in a right-handed conformation. However, during conditions of cellular stress, nucleic acids can also adopt an unusual, left-handed “Z-form”. These Z-nucleic acids, including Z-RNA and Z-DNA, are sensed by two proteins: ADAR1 and ZBP1. While ADAR1 binding to Z-nucleic acids prevents immune responses, activation of ZBP1 results in the activation of an innate immune response. It is clear, that ZBP1 has important functions in antiviral defence, cancer immunity and during autoinflammation, yet the mechanisms that govern its activation and which pathways downstream of ZBP1 are activated, is poorly understood. Additionally, a big hurdle currently preventing the molecular characterisation of ZBP1 signalling, is the lack of a selective ZBP1 agonist. I hypothesise that understanding the molecular mechanisms regulating ZBP1 activation and its downstream signalling pathways is fundamental for the development of therapeutics targeting this pathway. To test this hypothesis, I will address three major knowledge gaps in ZBP1 biology: (i) by purification of active ZBP1 complexes followed by nanopore sequencing and through solid-phase nucleic acid synthesis, I will generate a bona fide ZBP1 agonist, (ii) I will validate the ZBP1 agonist in vivo by testing its adjuvanticity in a mouse vaccination model, and (iii) by using a small compound and a genome-wide CRISPR/Cas9 knockout approaches, I will identify upstream and downstream regulators of ZBP1 signalling. Together, my proposed research plan will contribute to understanding the activation mechanisms of ZBP1, as well as its regulatory factors laying the foundation for understanding human ZBP1-driven (patho)physiology and development of therapeutic intervention.