Anaplastic lymphoma kinase is a receptor tyrosine kinase (RTK) that is important in regulating functions within the central nervous system <ref name=”Reshetnyak”>PMID:34819673</ref>. The route to the discovery of the structure of this protein was a rather complex one spanning almost 20 years with the kinase domain being discovered in 1994, the full protein structure in 1997, and the ligand structures discovered in 2014. These structures were found using [https://www.chemistryworld.com/news/explainer-what-is-cryo-electron-microscopy/3008091.article cryo-electron microscopy],[https://www.britannica.com/science/nuclear-magnetic-resonance nuclear magnetic resonance], and [https://www.sciencemuseum.org.uk/objects-and-stories/chemistry/x-ray-crystallography-revealing-our-molecular-world#:~:text=X%2Dray%20crystallography%20is%20a,called%20an%20x%2Dray%20camera. X-ray crystallography]. Anaplastic lymphoma kinase is a proto-oncogene with mutations associated with various types of cancers including non-small-cell lung cancer, anaplastic large cell lymphoma, squamous cell carcinoma, and inflammatory myofibroblastic cancer.