Crystal structures of IL-2-inducible T cell kinase complexed with inhibitors: insights into rational drug design and activity regulation.
Kutach, A.K., Villasenor, A.G., Lam, D., Belunis, C., Janson, C., Lok, S., Hong, L.N., Liu, C.M., Deval, J., Novak, T.J., Barnett, J.W., Chu, W., Shaw, D., Kuglstatter, A.(2010) Chem Biol Drug Des 76: 154-163
- PubMed: 20545945 
- DOI: https://doi.org/10.1111/j.1747-0285.2010.00993.x
- Primary Citation of Related Structures:  
3MIY, 3MJ1, 3MJ2 - PubMed Abstract: 
IL-2-inducible T cell kinase plays an essential role in T cell receptor signaling and is considered a drug target for the treatment of Th2-mediated inflammatory diseases. By applying high-throughput protein engineering and crystallization, we have determined the X-ray crystal structures of IL-2-inducible T cell kinase in complex with its selective inhibitor BMS-509744 and the broad-spectrum kinase inhibitors sunitinib and RO5191614. Sunitinib uniquely stabilizes IL-2-inducible T cell kinase in the helix C-in conformation by inducing side chain conformational changes in the ATP-binding site. This preference of sunitinib to bind to an active kinase conformation is reflective of its broad-spectrum kinase activity. BMS-509744 uniquely stabilizes the activation loop in a substrate-blocking inactive conformation, indicating that structural changes described for Src family kinases are also involved in the regulation of IL-2-inducible T cell kinase activity. The observed BMS-509744 binding mode allows rationalization of structure-activity relationships reported for this inhibitor class and facilitates further structure-based drug design. Sequence-based analysis of this binding mode provides guidance for the rational design of inhibitor selectivity.
Organizational Affiliation: 
Roche Palo Alto, 3431 Hillview Avenue, Palo Alto, CA 94304, USA.