GTP is constantly produced in the body, interacts with many proteins, and has various functions such as protein synthesis, proliferation, and signal transduction. Therefore, clarifying the amino acid residues and molecules to which GTP binds is important information not only for understanding the molecular mechanism but also for drug discovery. Our laboratory conducts high-throughput structural analysis by efficiently crystallizing proteins that are difficult to purify or crystallize using a mass culture system or an automatic crystallization system. The inositol phospholipid kinase PI5P4Kβ, a GTP sensor discovered in the GTP group, clarified the mechanism by which GTP interacts more strongly than ATP as well as ATP. We are also aiming to elucidate the intracellular functional mechanism of GTP signaling by performing structural analysis under conditions closer to the biological environment, including the membrane environment, using cryo-electron microscopy and nanodisc technology under development. There is also an environment for protein biochemical experiments such as isothermal calorimetry (ITC) and surface plasmon resonance (SPR).