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Updated: Jun 10, 2026
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
New insights into the mitochondrial nitric oxide production pathways
Kapuganti J Gupta1, Abir U Igamberdiev, Werner M Kaiser
1Julius-von-Sachs-Institut für Biowissenschaften, Würzburg, Germany. kapuganti@mpimp-golm.mpg.de
Plant Signaling & Behavior
|August 12, 2010
Summary
Mitochondria produce nitric oxide (NO) via nitrite reduction, not nitric oxide synthase (NOS). Barley root mitochondria also scavenge NO and convert it into other gaseous compounds.
Area of Science:
- Plant Physiology
- Mitochondrial Biology
- Biochemistry
Background:
- Nitric oxide (NO) is increasingly recognized as a crucial signaling molecule and metabolite in plants.
- Mitochondria are implicated as a significant site for NO production through nitrite reduction or nitric oxide synthase (NOS) pathways.
Purpose of the Study:
- To investigate and compare the mechanisms of NO production and scavenging by plant mitochondria.
- To elucidate the specific pathways involved in NO generation within barley root mitochondria.
Main Methods:
- Ozone collision chemiluminescence and DAF fluorescence assays were employed to detect and quantify NO.
- Mitochondrial fractions (membrane and matrix) were isolated to localize NO production.
- The effects of NOS inhibitors and substrates were analyzed.
Main Results:
- Nitrite reduction to NO was localized to the mitochondrial membrane fraction, not the matrix.
- Evidence for L-arginine dependent nitric oxide synthase (NOS) activity in barley root mitochondria was found to be untypical and doubtful.
- Mitochondria were confirmed to scavenge NO and convert it into gaseous intermediates (NO2, N2O, N2O3).
Conclusions:
- Barley root mitochondria primarily produce NO via nitrite reduction, with questionable NOS or NOS-like activity.
- Mitochondria play a dual role in NO metabolism, both producing and scavenging the molecule.
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