PI4KB (phosphatidylinositol 4-kinase beta) is a lipid kinase that generates phosphatidylinositol 4-phosphate (PI4P) at the Golgi and trans-Golgi network (TGN), serving as a critical hub for membrane trafficking and cellular signaling 1. The enzyme is recruited to membranes by adaptor proteins including ACBD3 and ARMH3, which enhance its catalytic activity 12. PI4KB regulates diverse cellular processes: it controls Golgi-derived vesicle trafficking of ATG9A for presynaptic autophagy 3, mediates Rab11a activation for ciliogenesis 4, and participates in infection-induced inflammation through STING activation and mitophagy 5. Oncogenic RAS induces non-canonical autophagy via phosphorylation of PI4KB at S256/T263 by ULK1 6, with elevated phosphorylation observed in colorectal and pancreatic cancers. PI4KB is required for SARS-CoV spike-mediated cellular entry, making it a broad-spectrum antiviral target 7. Mutations in PI4KB cause autosomal-dominant deafness 87, with disease variants abnormally intensifying PI4KB-Rab11a interactions and impairing ciliogenesis in inner ear cells 4. PI4KB inhibitors represent promising therapeutic agents for RAS-mutated cancers and viral infections.