Many drugs approved by the US Food and Drug Administration target cell membrane receptors. These receptors transduce extracellular signals into key physiological effects such as neurotransmission, taste, vision, and immune responses. However, abnormal receptor signaling can lead to various diseases. James Osei-Owusu wants to understand the molecular basis of how cell membrane receptors are activated and inhibited. He hopes to exploit these underlying mechanisms to improve drug development and disease treatments.