Expansion Microscopy: Protocols for Imaging Proteins and RNA in Cells and Tissues

Abstract

Expansion microscopy (ExM) is a recently developed technique that enables nanoscale‐resolution imaging of preserved cells and tissues on conventional diffraction‐limited microscopes via isotropic physical expansion of the specimens before imaging. In ExM, biomolecules and/or fluorescent labels in the specimen are linked to a dense, expandable polymer matrix synthesized evenly throughout the specimen, which undergoes 3‐dimensional expansion by ∼4.5 fold linearly when immersed in water. Since our first report, versions of ExM optimized for visualization of proteins, RNA, and other biomolecules have emerged. Here we describe best‐practice, step‐by‐step ExM protocols for performing analysis of proteins (protein retention ExM, or proExM) as well as RNAs (expansion fluorescence in situ hybridization, or ExFISH), using chemicals and hardware found in a typical biology lab. Furthermore, a detailed protocol for handling and mounting expanded samples and for imaging them with confocal and light‐sheet microscopes is provided. © 2020 The Authors.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 02, 2018
Source ID
10.1002/cpcb.56

Entities

People

  • Asmamaw T. Wassie
  • Edward Boyden
  • Fei Chen
  • Paul W. Tillberg
  • Ruixuan Gao
  • Shoh M Asano

Organizations

  • Army Research Office
  • Broad Institute
  • Howard Hughes Medical Institute
  • Intelligence Advanced Research Projects Activity
  • Janelia Research Campus
  • Massachusetts Institute of Technology
  • National Institutes of Health
  • Pfizer
  • United States Army Research Laboratory

Tags

Readers

  • Computer Vision.
  • Immunology and Pathology
  • Thin Film Deposition Science.