URI1 (unconventional prefoldin RPB5 interactor 1) is a prefoldin-like chaperone and scaffolding protein that regulates critical cellular processes including protein complex assembly, metabolic homeostasis, and tissue regeneration. URI1 functions as a core component of the PAQosome complex, which assembles macromolecular complexes and interacts with molecular chaperones 1. At the molecular level, URI1 binds and regulates glutamine synthase in hepatocytes, controlling glutamate levels to fine-tune liver regeneration through effects on macrophage metabolic reprogramming and YAP1-dependent hepatocyte proliferation 2. URI1 also modulates β-catenin signaling in intestinal stem cells, with reduced URI1 levels promoting c-MYC expression and tissue regeneration following ionizing radiation 3. Clinically, URI1 dysregulation associates with multiple diseases. URI1 is overexpressed in hepatocellular carcinoma, where HBx and c-MYC cooperatively induce its expression 4. In rheumatoid arthritis, lncRNA-mediated URI1 signaling promotes fibroblast-like synoviocyte proliferation and inflammation, which therapeutic agents can suppress 5. URI1 also participates in acute respiratory distress syndrome pathogenesis, with URI1 upregulation via CBX4 promoting mitophagy and reducing inflammation 6. Additionally, PAQosome components including URI1 regulate hepatic fibrosis through PI3K/AKT signaling 7, suggesting therapeutic potential in liver disease.