In genomes that form proteins or in proteins themselves, it is their intrinsic structure that determines their properties. When proteins bind to other proteins or hormones or when they enable cells to function in a specific manner, this is also the result of their inherent structure. It is no exaggeration to say that the fundamental functions that sustain human life are all determined by how genomes are structured. Even cancer can be traced back to changes in the structure of biological matter.

The Structural Biology of Cancer Lab, directed by Professor Yunje Cho at the Department of Life Sciences, POSTECH, primarily engages in the observation of how biological matter – like genomes within the human body and proteins on the cell membrane – maintain homeostasis. Leveraging structural biology that identifies the structure of biological matter to discover their features and principles, researchers at the Lab are broadening the boundary of their endeavors from genomes to cell membrane proteins.

Recently, the Lab has been focusing on G-protein coupled receptors (GPCRs) located on the cell membrane. This led to an unprecedented discovery regarding the structure and activation mechanism of a Class C GPCR. Cells use G proteins for information transmission. When GPCRs detect external signals, they combine with intracellular G proteins to activate the cell’s information transmittance system. There are approximately 800 GPCRs within the human body, of which roughly 100 remain unidentified in their structure or activation principle. This naturally makes these ‘orphan receptors’ a potential area for intensive future research.

The Lab is also studying receptors for insulin, a hormone used to curb diabetes. Insulin injections have the power to spur continuous cell growth, which could ultimately cause cancer in the process. Analyzing the signal transmission system at the cellular level could improve efficiency in absorbing glucose while blocking signals that trigger cancerous growth. Another main research topic concerns ‘GABA receptors’ that work as an inhibitory neurotransmitter.

The Pohang Accelerator Laboratory equipped with the Pohang Light Source and the PAL-XFEL, the third and fourth generation synchrotrons respectively, offers a significant advantage in conducting structural biology research. These advanced synchrotrons provide scientists with a thorough and detailed view into the structure of protein with the help of synchrotron light. “POSTECH has three electron microscopes within its premises”, Professor Cho commented, adding “Our school is equipped with a highly competitive infrastructure that is recognized globally”.

While structural biology research has traditionally lent itself to the realm of basic research, it has morphed to encompass much more direct and practical benefits to society as it has recently produced notable outcomes in drug development. More than a quarter of the top 200 new drugs being sold globally target GPCRs. “While our research may not directly correlate with drug development, it certainly provides useful information to expedite the entire process of discovering drugs”, Professor Cho mentioned, and went on to say “I’m confident that we are closer to realizing our goals than ever before”.