After the discovery of the structure of DNA by Rosalind Franklin and Watson and Crick using X-ray diffraction, biologists and biochemists have moved on to look at more complicated structures, including the study of very large protein molecules.
Proteins play vital roles in the body, from catalyzing chemical reactions to controlling most of the work that occurs in our cells. Proteins are constructed from chains of thousands of smaller units called amino acids. Only 20 different types of amino acids exist, but the sequence of these amino acids can dramatically affect the 3D shape of the protein, and hence its function. It is therefore key that we can work out the 3D structure of the protein using crystallography to try and determine the protein’s function, and for the potential of drug design.
Recent work at the Diamond Light Source has unlocked the structure of the corticotropin-releasing factor receptor 1 (CRF1), known to control our response to stress. This new structural discovery opens many opportunities for new drugs to be developed to treat depression, diabetes and osteoporosis. This type of protein is known as a G-protein-coupled receptor (GPCR). GPCRs are found in cell membranes within the body, and are involved in a broad range of biological processes across cell membranes. Most clinically used drug molecules bind to these GPCRs to evoke their biological effect. It is therefore key to try to determine the structure of these materials at the molecular level to be able to design new drug targets. In 2012, Robert Lefkowitz and Brian Kobilka were jointly awarded the Nobel prize in chemistry for groundbreaking discoveries into the inner workings of GPCRs.