Claudiu Gradinaru

Gradinaru biophysics research laboratory uses advanced laser and detection technology to capture conformational dynamics and molecular interactions at the single-molecule level. Single-molecule techniques are widely applied in life sciences and nanotechnology due to their unique ability to go beyond the intrinsic disorder and complexity of biological systems and provide new insights for how they work and for therapeutic intervention. Ultrasensitive microscopes in our lab, designed and built specifically for single-molecule fluorescence imaging and spectroscopy, provide a wide range of photon-level experimental capabilities, making the lab unique in Canada. Currently, the Gradinaru lab focuses on two main directions of research. First, we integrate single-molecule fluorescence data with other structural data (NMR, SAXS) and polymer physics theory to understand the determinants of “fuzzy structures” in biology and how intrinsically-disordered proteins (IDPs) interact with other molecules. Second, we measure nanometer-scale distances and nanosecond-to-second dynamics in G protein coupled-receptors (GPCRs), a large class of membrane proteins that are the main target of medicinal drugs. Our goal is to define how/when/where GPCRs activate and oligomerize in the cell membrane and how their innate structural flexibility couples to quaternary organization and biased signaling.