Related Experiment Videos
T-2 mycotoxin inhibits mitochondrial protein synthesis
J G Pace1, M R Watts, W J Canterbury
1Pathophysiology Division, U.S. Army Medical Research Institute of Infectious Diseases, Ft. Detrick, Frederick, MD 21701-5011.
Abstract:
We investigated the effect of T-2 toxin on rat liver mitochondrial protein synthesis. Isolated rat liver mitochondria were supplemented with an S-100 supernatant from rat liver and an external ATP-generating system. We used an in vitro assay employing cycloheximide, an inhibitor of cytoplasmic protein synthesis, and chloramphenicol, an inhibitor of mitochondrial protein synthesis, to distinguish mitochondrial protein synthesis from the cytoplasmic process. Amino acid incorporation into mitochondria was dependent on the concentration of mitochondria and was inhibited by chloramphenicol. The rate of uptake of [3H]leucine into mitochondrial protein was unaffected by the addition of T-2 toxin and was not a rate-limiting step in incorporation. However, 0.02 micrograms/ml of T-2 toxin decreased the rate of protein synthesis by isolated mitochondria by 50%. The degree of protein synthesis inhibition correlated with the amount of T-2 toxin taken up by the mitochondria. While T-2 toxin is known to inhibit eukaryotic protein synthesis, this is the first time T-2 was shown to inhibit mitochondrial protein synthesis.
Insights
T-2 toxin significantly inhibits mitochondrial protein synthesis in rats. This study demonstrates T-2 toxin
Area of Science:
- Biochemistry
- Toxicology
- Cell Biology
Background:
- Mitochondria are crucial for cellular energy production.
- Mitochondrial protein synthesis is essential for mitochondrial function.
- T-2 toxin is a known inhibitor of eukaryotic protein synthesis.
Purpose of the Study:
- To investigate the effects of T-2 toxin on mitochondrial protein synthesis.
- To determine if T-2 toxin directly inhibits protein synthesis within isolated rat liver mitochondria.
Main Methods:
- Isolated rat liver mitochondria were used for in vitro assays.
- Cycloheximide and chloramphenicol distinguished mitochondrial from cytoplasmic protein synthesis.
- Amino acid incorporation ([3H]leucine) measured protein synthesis rates.
Main Results:
- Mitochondrial protein synthesis was confirmed and inhibited by chloramphenicol.
- T-2 toxin (0.02 µg/ml) reduced mitochondrial protein synthesis by 50%.
- Inhibition correlated with T-2 toxin uptake by mitochondria; leucine uptake was unaffected.
Conclusions:
- T-2 toxin directly inhibits mitochondrial protein synthesis.
- This is the first evidence of T-2 toxin affecting mitochondrial protein synthesis.
- T-2 toxin poses a risk to mitochondrial function and cellular health.