Professor Senyon Choe and his colleagues also study the relationship between a molecule's fine structure and the functions it carries out. Among Choe's recent interests is the study of molecules that bind to specific cells to instruct them to carry out functions. The premise that “form follows function” became a mantra for numerous leading architects and industrial designers during a good part of the last century. In biology, evolution operates according to a similar premise because forms with better functionality are likelier to be selected. Trying to understand the relationship between a molecule’s fine structure and the functions it carries out, Choe and his colleagues use x-ray crystallography and NMR spectroscopy to zoom in on ion channels and receptors in the cell membrane to visualize how they interact with messenger proteins. Recent work focused on analyzing the three-dimensional structure of a whole protein complex to illustrate how TGF-beta, a messenger molecule that plays a role in cancer, the immune system and heart disease, binds to its receptor molecules on specific target cells to instruct them to do its bidding. An extension of this work explores the possibility of designing new messages to instruct cells to carry out non-natural processes such as coaxing differentiated cells back into an immature, pluripotent state. These types of newly created messages will have tremendous clinical potential as guiding molecules