Identify new mediators of proinflammatory cytokine signaling

PROJECT SUMMARY Proinflammatory cytokines are key players in innate immune responses. Dysregulation of proinflammatory cytokines is associated with a number of human diseases such as arthritis, cardiovascular diseases, and metabolic disorders. In particular, the proinflammatory cytokines interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNFα) interfere with important cellular signaling pathways such as AKT signaling and disrupt physiological processes dependent on the signaling pathways. It remains poorly understood how IL-1β and TNFα compromise AKT signaling at the molecular level. In this exploratory project, we will address this key question by identifying mediators of cytokine-induced inhibition of AKT signaling, which regulates a range of physiological responses. In our preliminary studies, we developed assays to measure the inhibitory effects of IL-1β and TNFα on AKT signaling. Moreover, using RNA-Seq, we identified genes upregulated or downregulated in cytokine-treated cells. We also developed CRISPR screening platforms to genetically dissect complex biological pathways at the genomic scale. In this project, we will capitalize on these preliminary data to perform genome-wide genetic screens to identify factors mediating cytokine-induced inhibition of AKT signaling. Next, we will validate candidate genes identified in the screens using pooled secondary screens and individual gene validation. Finally, we will gain mechanistic insights into the molecular functions of selected factors identified in the screens. If successfully accomplished, this exploratory project will provide key insights into cytokine-induced inhibition of cellular signaling and will facilitate the development of new therapeutics for cytokine-linked diseases.