Functional investigation of cell metabolism signaling using chemical proteomics

The work presented in this dissertation utilizes chemical proteomics to dissect the complexities of cellular metabolism, spanning lipid signaling pathways implicated in immune response and pain, to the intricate RNA dynamics involved in cell stress. We delve into the role of Diacylglycerol lipase-beta (DAGLβ) in macrophage function, revealing that inactivation of DAGLβ not only reduces pro-inflammatory lipid signaling but also activates the LKB1-AMPK pathway, reprogramming the phosphoproteome and bioenergetics. Furthermore, the observed anti-nociceptive behavior in mice was associated with the activation of AMPK, which was induced by the inhibition of DAGLβ in vivo. This discovery illuminates a novel interaction between endocannabinoid biosynthesis and energy regulation, offering insights into the modulation of inflammatory and pain responses. Concurrently, our research extends to the realm of RNA metabolism, where we develop chemical tools to modulate ribonucleoprotein (RNP) granules, such as stress granules (SGs) and processing bodies (PBs), pivotal in cellular stress, viral infection, and tumor dynamics. By employing a combined immunofluorescence screening with chemoproteomics, we identify sulfonyl-triazoles that modulate SG and PB formation, by targeting RNA-binding domains and protein-protein interactions. We spotlight the functional impact on G3BP1 Y40, a key site in SG assembly, unveiling the potential of chemical probes in disrupting pathological SG formation. Collectively, our integrated approach reveals new vistas in the regulation of cellular metabolism, underpinning the development of therapeutic strategies targeting metabolic and stress-related cellular pathways.