Lab visit to the New York University

Single-Molecule Localization Microscopy (SMLM) has emerged as a leading super-resolution imaging approach for nanoscale visualization of molecular structures in cells. During the periods of visiting in the lab of Prof. Rothenberg at New York University, Xuzhu Zhang was trained to perform SMLM experiments regarding on DNA damage response (DDR) of U2OS cells under the treatment of chemical drug Hydroxyurea (HU). In comparison with conventional fluorescence microscopy, SMLM provides much more details on spatial structures of DNA, proteins, as well as their colocalization within a single nucleus. By analyzing the images using the auto-pair correlation method for SMLM, researchers quantitatively determined the molecular density of nacent DNA (labeled by EdU) and immunofluorescence-labeled proteins such as RNase, TOP1, and PCNA in each nucleus. They found that EdU and RNase density decreased gradually (Fig. 1(E, F)) as the increase of HU concentrations (from 0 to 0.5 µM), demonstrating the reduction of nacent DNA and RNase concentrations due to the stalled DNA replication resulted from HU treatment. These preliminary results provide the experimental basis for the future study of DNA repair in cancer therapy at the single-molecule level.

Visitor

Xuzhu Zhang

Dates

Nov.25, 2018 – Mar. 9, 2019

Location

New York University, USA