Paul C. Cross Endowed Lecture in Physical Chemistry Professor Xiaowei Zhuang – Department of Chemistry & Chemical Biology, Harvard University; Howard Hughes Medical Institute Investigator Illuminating biology at the nanoscale and genome scale by imaging As the fundamental unit of life, a cell is comprised of numerous types of molecules that form intricate interaction networks. Dissecting the inner workings of a cell thus requires imaging with molecular-scale resolution such that these molecular interactions can be directly visualized. However, the diffraction-limited resolution of light microscopy is substantially larger than molecular length scales in cells, making many sub-cellular structures difficult to visualize. Another major challenge in imaging is the low throughput in the number of molecular species that can be simultaneously imaged, while genome-scale throughput (i.e. the ability to simultaneously image thousands of molecular species) is needed for addressing systems level questions. In this talk, I will describe two imaging methods that we developed to overcome these challenges and biological applications of these methods. I will first describe STORM, a super-resolution imaging method that overcomes the diffraction limit and allows imaging of molecular structures in cells with nanometer-scale resolution. I will present both technology development of and recent biological discoveries enabled by STORM with a focus on the latter. I will then describe MERFISH, a single-cell transcriptome and genome imaging method that enables imaging of RNA and DNA at the genome scale, which in turn allows mapping of the spatial organization of the transcriptome and genome inside cells and the organization of distinct types of cells in complex tissues. Host: Joshua Vaughan |