David Farrens, PhD

Photo of Dr. David Farrens

Physical and biochemical studies of G-Protein coupled receptors


My lab studies G-protein coupled receptors (GPCRs), the large family of membrane proteins crucial for transmitting signals into cells.  Our work primarily focuses on two GPCRs, the visual photoreceptor rhodopsin, and CB1, the "marijuana receptor".  We study the structure and dynamics of these receptors, and how they interact with their affiliate signaling partners (G-proteins, kinases and arrestins).

We use a combination of physical and biochemical techniques in our studies. One especially powerful approach, called site-directed fluorescence labeling (SDFL), involves introducing fluorescent probes at defined locations in the receptor to determine where, when and what kinds of conformational changes occur, thus yielding unique insights that can be difficult to obtain by other methods.  We also develop new SDFL methods, and have helped establish the use of bimane, a small, non-perturbing fluorescent label, as an ideal probe for SDFL studies. 

Ultimately our goal is to identify common structural mechanisms involved in GPCR mediated signal transduction and regulation.  We feel an intense focus on these receptors is justified - the majority of drugs in use today work by affecting GPCR signaling. Thus, a better understanding of how GPCRs are activated will help guide and improve future drug development.