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Genetic Oxygen Sensor

GFP as an indicator of intracellular oxygenation
  • Eiji Takahashi
  • Tomohiro Takano
  • Aya Numata
  • Natsuho Hayashi
  • Satoshi Okano
  • Osamu Nakajima
  • Yasutomo Nomura
  • Michihiko Sato
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 566)

Abstract

We report in this article a new method for in vivo oxygen measurement using green fluorescence protein (GFP). COS7 cells were transiently transfected with an expression vector, pCMX-GFP, using a polyethylenimine reagent and cultured for 48 hrs. After exposure of the cell to anoxic gas (O2<.001%), a 1 min illumination of the cell to strong 470–490 nm light evoked a significant red fluorescence (excitation 520–550 nm, emission >580 nm) that had been negligible before the photoactivation. This red shift of (green) GFP fluorescence was never observed in normoxia. We then examined the validity of this method in transgenic mice in which GFP is stably expressed (green mice). All the ventricular myocytes isolated from the green mice showed significant green fluorescence, although the intensity was ∼1/200 of the transiently GFP-expressing COS7 cells. The photoactivation in anoxia increased the red fluorescence in these cells, but the magnitude was much smaller than expected. In summary, GFP can be used as an in situ probe for hypoxia. In GFP-expressing transgenic animals, in vivo imaging of anoxic loci with a submicron spatial resolution may be possible.

Keywords

Ventricular Myocytes Green Fluorescence Protein Fluorescence Photo Activation Significant Green Fluorescence Oxygen Indicator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • Eiji Takahashi
  • Tomohiro Takano
  • Aya Numata
  • Natsuho Hayashi
  • Satoshi Okano
  • Osamu Nakajima
  • Yasutomo Nomura
  • Michihiko Sato

There are no affiliations available

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