Spatial distribution and structural arrangement of a murine cytomegalovirus glycoprotein detected by SPDM localization microscopy

Histochem Cell Biol. 2014 Jul;142(1):61-7. doi: 10.1007/s00418-014-1185-2. Epub 2014 Feb 7.

Abstract

Novel approaches of localization microscopy have opened new insights into the molecular nano-cosmos of cells. We applied a special embodiment called spectral position determination microscopy (SPDM) that has the advantage to run with standard fluorescent dyes or proteins under standard preparation conditions. Pointillist images with a resolution in the order of 10 nm can be obtained by SPDM. Therefore, vector pEYFP-m164, encoding the murine cytomegalovirus glycoprotein gp36.5/m164 fused to enhanced yellow fluorescent protein, was transiently transfected into COS-7 cells. This protein shows exceptional intracellular trafficking dynamics, moving within the endoplasmic reticulum (ER) and outer nuclear membrane. The molecular positions of gp36.5/m164 were visualized and determined by SPDM imaging. From the position point patterns of the protein molecules, their arrangements were quantified by next neighbour distance analyses. Three different structural arrangements were discriminated: (a) a linear distribution along the membrane, (b) a highly structured distribution in the ER, and (c) a homogenous distribution in the cellular cytoplasm. The results indicate that the analysis of next neighbour distances on the nano-scale allows the identification and discrimination of different structural arrangements of molecules within their natural cellular environment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / chemistry
  • COS Cells
  • Cells, Cultured
  • Chlorocebus aethiops
  • Glycoproteins / analysis*
  • Glycoproteins / genetics
  • Luminescent Proteins / chemistry
  • Mice
  • Microscopy, Fluorescence
  • Muromegalovirus / chemistry*
  • Viral Envelope Proteins / analysis*
  • Viral Envelope Proteins / genetics

Substances

  • Bacterial Proteins
  • Glycoproteins
  • Luminescent Proteins
  • Viral Envelope Proteins
  • yellow fluorescent protein, Bacteria