Related Experiment Videos
Mitochondrial inclusions and mitochondrial respiratory function in selenite-treated mammary epithelial cell lines
D G Morrison1, D F Pauly, R C Berdan
1Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Abstract:
The effect of selenite on mitochondrial morphology, selenoprotein synthesis, membrane potential, phosphorylating respiration, P/O ratio and respiratory control index were evaluated relative to selenite inhibition of DNA synthesis in murine mammary epithelial cell lines. No inhibition of mitochondrial function was noted. Mitochondrial inclusions and most mitochondrial specific selenoproteins were not observed until after DNA synthesis was inhibited. Pyruvate, methionine, hydroxybutyrate, dexamethasone or carnitine had no effect on the inclusions. The results provide evidence for the hypothesis emphasizing the importance of cytosolic selenoproteins modulating the growth inhibitory effects of selenite.
Insights
Selenite did not inhibit mitochondrial function in mammary cells. Cytosolic selenoproteins, not mitochondrial ones, appear to modulate selenite
Area of Science:
- Cell Biology
- Biochemistry
- Toxicology
Background:
- Selenite is known to affect cellular processes.
- Understanding selenite's impact on cell growth and function is crucial.
Purpose of the Study:
- To investigate the effects of selenite on mitochondrial function and selenoprotein synthesis in murine mammary epithelial cells.
- To determine the relationship between selenite's effects on mitochondrial function and its inhibition of DNA synthesis.
Main Methods:
- Murine mammary epithelial cell lines were treated with selenite.
- Mitochondrial morphology, membrane potential, and respiratory functions were assessed.
- Selenoprotein synthesis and DNA synthesis were measured.
Main Results:
- No inhibition of mitochondrial function was observed following selenite treatment.
- Mitochondrial inclusions and mitochondrial-specific selenoproteins appeared only after DNA synthesis inhibition.
- Cytosolic selenoproteins, rather than mitochondrial ones, were implicated in modulating selenite's growth inhibitory effects.
Conclusions:
- Selenite's primary impact on mammary cells involves inhibition of DNA synthesis, not mitochondrial function.
- Cytosolic selenoproteins play a key role in mediating the growth inhibitory effects of selenite.
- Further research into cytosolic selenoprotein function is warranted.