Executive Summary : | Membrane receptors for extracellular ligands organize into oligomeric structures. How their oligomeric arrangement affects the propagation of signals from outside to the inside of the cell, has been a challenge since hardly any tools are available to observe or alter the organization and dynamics of these complexes at the nanoscale. Using DNA nanotechnology and protein bioengineering, we will develop new tools to probe (e.g. DNA functionalized quantum dots) and program (e.g. DNA-scaffolded multivalent ligands) the organization of these receptors with a focus on membrane receptors to understand their organization, and how their dynamical organization contributes to physiological pathways and disease. I will develop DNA nanotechnology based toolbox for in situ imaging proteomics with quantum dots loaded DNA cage functionalized with cellular ligands for labelling receptors from the level of single molecules in single cells to whole networks in tissues. I will first concentrate on technology development both in terms of hard- and software as well as molecular imaging tools and innovative labeling approaches. I will construct cutting-edge quantum dots loaded DNA cages which can be functionalized with practically any bio-tag, and probe their biological behavior; enabling high-speed, whole cell and deep tissue imaging with advanced bioimaging. I will develop DNA-based imaging probes that allow rapid high-content screening with super-resolution imaging like PAINT. This will make the unique multiplexing features of DNA-QD-PAINT available to broader community. In later part, I will devise novel, transformative approaches for quantitative and barcode-based proteomics imaging. This will bring quantitative system biology to the single-cell level. The challenge of achieving modular and highperformance labeling for proteins will be overcome by developing innovative DNA cages carrying QDs coupled to ligands. DNA nanotechnology based ligands will potentially decipher the interplay of whole surface receptor families and downstream signaling pathways. This will allow to combine high-resolution localization information with proteomics. I will develop 3D devices from DNA which carrying a small bright nanoparticle. These are attached to a small tag that can bind to target proteins on cell surface. We can image individual protein molecules on cells using microscopes. We can then ask how different proteins behave on cell surface and what happens to them when they go inside the cells. We can ask how normal body cells are different from diseased cells and how proteins within these different cell types behave. In summary, I aim to develop DNA based multi-dimensional bioimaging ligands that could probe, program and reprogram the organization of receptors on the plasma membranes of the cells, leading to very controlled signal transduction which can trigger processes like endocytosis, signaling, migration and differentiation. |