YM-201636 is primarily used as a selective inhibitor of phosphatidylinositol 4-kinase III beta (PI4KIIIβ), making it a valuable tool in studying intracellular signaling pathways involving phosphoinositides. It is widely applied in cell biology research to probe the role of PI4KIIIβ in membrane trafficking, particularly in the Golgi apparatus and trans-Golgi network. Due to its inhibitory effect on PI4KIIIβ, YM-201636 disrupts the production of phosphatidylinositol 4-phosphate (PI4P), which affects vesicular transport and secretory pathway function. This compound has also been investigated for its antiviral properties, as inhibition of PI4KIIIβ can interfere with the replication machinery of certain RNA viruses, including enteroviruses and hepatitis C virus, which rely on PI4P-enriched membrane compartments for replication. Additionally, YM-201636 has been used to explore the connection between lipid kinase activity and autophagy, showing potential in modulating autophagosome formation in specific cellular contexts. Its application remains mainly in preclinical research, where it serves as a pharmacological agent to dissect lipid kinase functions and assess the therapeutic potential of targeting PI4K pathways.