Mallinckrodt Professor of Chemistry and Chemical Biology
12 Oxford Street
Department of Chemistry and Chemical Biology
Cambridge, MA 02138
Lab Size: Greater than 20
Recently we have taken the single-molecule experiment to live cells and have begun real-time imaging of gene expression, both at the transcriptional and translational level. To accomplish this, we have developed several strategies to achieve single-molecule sensitivity with high specificity, millisecond time resolution, and nanometer precision in a living cell. We have observed protein being generated one molecule at a time in E. coli cells, and studied how a transcription factor binds to DNA and regulates gene expression. We found that a single-molecule event can be solely responsible for the life changing decision of a cell.
Finally, we continue to push for state-of-the-art techniques for imaging intracellular dynamics. Our group has led in the rapid development of coherent anti-Stokes Raman scattering (CARS) microscopy, which allows imaging of live cells and organisms based on vibrational spectroscopy. This allows noninvasive imaging of small molecules, such as metabolites and drugs, without the introduction of natural or artificial fluorophores. Meanwhile, CARS is becoming a powerful imaging method for biomedicine. For example, it enables imaging of skin at the video rate, mapping the distribution of lipids, water and drug molecules, as well as brain tissue with the ability to identify brain tumors.
We are in a new era, when biology is becoming a data-rich and quantitative science with a wealth of physical and chemical tools. Our group is thrilled to be able to make both scientific and technological contributions to the biomedical field at this exciting time.
Blainey, Paul C.; Luo, Guobin; Kou, S.C.; Mangel, Walter F.; Verdine, Gregory L.; Bagchi, Biman; Xie, X. Sunney "Nonspecifically bound proteins spin while diffusing along DNA" Nature Structural & Molecular Biology, 16, 1224-1229 (2009).
Lu, Ju; Min, Wei; Conchello, Jose-Angel; Xie, X. Sunney; Lichtman, Jeff W. "Super-Resolution Laser Scanning Microscopy through Spatiotemporal Modulation" Nano Letters, 9, 3883-3889 (2009).
Min, Wei; Lu, Sijia; Holtom, Gary R.; Xie, X. Sunney "Triple-Resonance Coherent Anti-Stokes Raman Scattering Microspectroscopy" ChemPhysChem, 10, 344-347 (2009).
Murugkar, S.; Evans, C.L.; Xie, X.S.; Anis, H. "Chemically specific imaging of cryptosporidium oocysts using coherent anti-Stokes Raman scattering (CARS) microscopy" Journal of Microscopy, 233, 244-250 (2009).