Cristae dynamics is modulated in bioenergetically compromised mitochondria.

Mitochondrial cristae are dynamic structures that influence energy production. Recent studies have shown that these membranes can merge and split within mitochondria. However, the factors controlling these changes remain unclear. Prior research has established that cristae structure supports oxidative phosphorylation. Yet, it was unknown whether bioenergetic status affects cristae dynamics. This gap motivated an investigation into how OXPHOS complexes and mitochondrial membrane potential influence cristae behavior. The role of ADP/ATP translocation in this process had not been fully explored. Existing knowledge suggested a link between cristae morphology and metabolic function. However, no prior work had resolved how specific bioenergetic conditions modulate cristae dynamics. This uncertainty drove the need for a detailed study using advanced imaging techniques.

The study aimed to determine how bioenergetic conditions affect cristae dynamics. Researchers focused on oxidative phosphorylation complexes and mitochondrial membrane potential. They also examined the role of ADP/ATP translocation in cristae remodelling. The goal was to identify whether these factors influence cristae morphology and movement. The study sought to clarify if cristae dynamics depend on ΔΨm or ATP levels. By using live-cell imaging, the team could observe real-time changes in cristae structure. This approach allowed them to test the effects of various inhibitors on mitochondrial function. The findings would help understand the interplay between bioenergetics and cristae dynamics.

The researchers used live-cell STED nanoscopy to capture detailed images of cristae. They treated mammalian cells with rotenone, antimycin A, oligomycin A, and CCCP. These compounds inhibit OXPHOS complexes and ATP exchange. STED imaging allowed them to track changes in cristae morphology and movement. Quantitative analysis was performed to measure cristae density and dynamics. The team compared results under different bioenergetic conditions. They assessed mitochondrial membrane potential and ATP levels after treatment. This combination of imaging and biochemical analysis provided insights into cristae behavior.

Cristae dynamics were not impaired by OXPHOS inhibition or reduced ATP levels. In fact, CCCP treatment increased cristae dynamics despite ΔΨm loss. Enlarged mitochondria and reduced cristae density were observed after drug treatments. ADP/ATP translocation inhibition caused abnormal cristae morphology in some mitochondria. Cristae dynamics remained intact when OXPHOS complexes were blocked. ΔΨm abrogation led to enhanced cristae movement, indicating independence from ΔΨm. The study showed that cristae dynamics are not strictly dependent on bioenergetic status. These findings suggest a complex relationship between metabolism and cristae remodelling.

The study found that cristae dynamics are not strictly regulated by OXPHOS or ΔΨm. Inhibition of ATP exchange led to morphological changes in cristae. However, OXPHOS inhibition did not impair cristae movement. These results suggest that cristae dynamics are modulated by multiple factors. The findings support an interplay between bioenergetics and cristae remodelling. The role of ADP/ATP translocation in cristae structure was confirmed. The study provides quantitative evidence of cristae behavior under different conditions. These conclusions align with the observed effects of various inhibitors on mitochondrial function.