Related Experiment Video

Updated: Aug 24, 2026

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells
08:32

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Published on: March 16, 2017

Protection from the dark side of NO: signaling and cellular defenses against nitric oxide toxicity

Bruce Demple1

  • 1Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, MA 02115, USA. bdemple@hsph.harvard.edu

IUBMB Life
|April 17, 2004
PubMed

Insights

Cellular resistance to nitric oxide (NO) toxicity involves inducible defense pathways. The enzyme heme oxygenase-1 (HO1) is crucial, with its mRNA stabilization playing a key role in NO resistance.

Area of Science:

  • Biochemistry
  • Cell Biology
  • Toxicology

Background:

  • Nitric oxide (NO) is vital for intercellular signaling and inflammation but can harm non-target cells due to poor membrane containment.
  • Cellular defense mechanisms are activated to mitigate NO-induced damage, prevent apoptosis, and enhance repair systems.

Purpose of the Study:

  • To investigate the genetic and biochemical basis of cellular resistance to nitric oxide (NO) toxicity.
  • To identify the critical heme oxygenase-1 (HO1)-dependent reactions conferring NO resistance.

Main Methods:

  • Studied inducible resistance mechanisms in cellular models.
  • Analyzed the role of heme oxygenase-1 (HO1) in NO-mediated cytotoxicity.
  • Investigated transcriptional activation and mRNA stabilization of HO1 in response to NO exposure in human fibroblasts.

Main Results:

  • Heme oxygenase-1 (HO1) activity is essential for mammalian cell resistance to NO.
  • HO1 induction by NO involves transcriptional activation and, notably, NO-induced mRNA stabilization.
  • mRNA stabilization of HO1 increases with NO exposure levels in human fibroblasts.

Conclusions:

  • Inducible NO resistance pathways are complex, involving novel regulatory mechanisms.
  • Heme oxygenase-1 (HO1) mRNA stabilization is a critical component of cellular defense against NO toxicity.
  • Understanding these pathways offers insights into cellular responses to oxidative stress.

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