Delaying Photobleaching of a Light-Switch Complex for Real-Time Imaging of Single Viral Particle Uncoating

Anal Chem. 2016 Nov 1;88(21):10675-10679. doi: 10.1021/acs.analchem.6b03127. Epub 2016 Oct 18.

Abstract

Photobleaching is a major obstacle in the real-time imaging of biological events, particularly at the single-molecule/particle level. Here, we report a strategy to delay photobleaching of a light-switch complex, [Ru(phen)2dppx]2+, by insertion of a six-cysteine peptide into virus particles. The six-cysteine peptide was inserted into viral protein R of HIV-1 and assembled into infectious HIV-1 viral particles, where it effectively delayed the photobleaching of the [Ru(phen)2dppx]2+ complex used to label viral genomic RNAs. This delay in photobleaching allowed for a monofluorescent assay to be constructed for the real-time monitoring of viral uncoating, a poorly understood process. This novel strategy to delay photobleaching in infectious viral particles provides a powerful method to analyze viral uncoating at the single-particle level in real time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Coordination Complexes / chemistry
  • Coordination Complexes / radiation effects*
  • Cysteine / genetics
  • Fluorescent Dyes / chemistry
  • Fluorescent Dyes / radiation effects*
  • HEK293 Cells
  • HIV-1 / genetics
  • HIV-1 / metabolism*
  • HeLa Cells
  • Humans
  • Microscopy, Confocal / methods
  • Microscopy, Fluorescence / methods
  • Peptides / genetics
  • Photobleaching*
  • RNA, Viral / chemistry
  • Recombinant Fusion Proteins / genetics
  • Ruthenium / chemistry
  • Virus Uncoating*
  • vpr Gene Products, Human Immunodeficiency Virus / genetics

Substances

  • Coordination Complexes
  • Fluorescent Dyes
  • Peptides
  • RNA, Viral
  • Recombinant Fusion Proteins
  • vpr Gene Products, Human Immunodeficiency Virus
  • Ruthenium
  • Cysteine