Mitochondria siphon oxygen from chloroplasts, study finds
Mar 6th 2026
University of Helsinki researchers found that when mitochondrial respiration increases it can lower oxygen inside chloroplasts, changing photosynthetic chemistry and helping plants adjust to stress.
- Study led by Dr. Alexey Shapiguzov at the University of Helsinki and published in Plant Physiology shows mitochondria can draw molecular oxygen away from chloroplasts.
- Researchers used genetically modified Arabidopsis with mitochondrial defects that activate alternative respiratory enzymes to boost mitochondrial oxygen consumption.
- Increased mitochondrial respiration lowered tissue oxygen and made chloroplasts resistant to methyl viologen by limiting available oxygen for the chemical to act on.
- Exposing plants to nitrogen to create low oxygen conditions sharply reduced methyl viologen activity, confirming oxygen limitation as the mechanism.
- The discovery reveals a new intracellular oxygen exchange that affects photosynthesis and stress responses and could inform crop resilience research and new imaging methods.