Seminars

DEPARTMENT OF CHEMISTRY, SEOUL NATIONAL UNIVERSITY.

Ultrastructural and Spectroscopic Studies by Single-Molecule Super-Resolution Imaging

February 23, 2018l Hit 465
Date : April 5, 2018 16:30 ~
Speaker : Prof. Doo Ry Kim(Hanyang University)
Location : Mogam Hall, Bldg 500
Fluorescence light microscopy (LM) and electron microscopy (EM) are two of the most widely used imaging modalities for probing cellular structures. In particular, recent development of super-resolution fluorescence microscopy allows the location of molecules to be determined with nanometer-scale spatial resolution. In the first part of this talk I present my works in developing methods of several correlative super-resolution fluorescence light microscopy (LM) and electron microscopy (EM) assays by combining stochastic optical reconstruction microscopy (STORM). Here, I have developed several experiment protocols for correlative stochastic optical reconstruction microscopy (STORM) and EM methods, both for un-embedded samples by applying EM-specific sample preparations after STORM imaging and for embedded and sectioned samples by optimizing the fluorescence under EM fixation, staining and embedding conditions. I demonstrated these methods using a variety of cellular targets. In the second part of the talk, I present my work in applying super-resolution microscopy to investigate the distributions and interactions of purine biosynthetic enzymes organization complex called purinosomes within the cell. We use single-cell super-resolution and confocal microscopy to characterize purinosome localization and motions in HPRT-deficient LND (Lesch–Nyhan syndrom) fibroblasts and provide insights into how purinosomes meet a cell’s purine demand. Our results highlight how purinosomes are further spatiotemporally organized in cells by their dynamic interplay with mitochondria and microtubules. Lastly, I will present my recent work in single-molecule spectroscopy, namely spectrally resolved stochastic optical reconstruction microscopy (SR-STORM). By recording both the images and emission spectra of thousands of single fluorescent molecules stochastically generated from the ring-opening reaction of a spiropyran, we provide mechanistic insights into its multi-path reaction pathways.