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What physiological role(s) does the alternative oxidase perform in animals?
Howard T Jacobs1, J William O Ballard2
1Faculty of Medicine and Health Technology, FI-33014 Tampere University, Finland; Department of Environment and Genetics, La Trobe University, Melbourne, Victoria 3086, Australia.
Biochimica Et Biophysica Acta. Bioenergetics
|April 3, 2022
Summary
The alternative oxidase (AOX) may help animals resist various stresses, but its exact function and loss in some groups require further study. Understanding AOX
Area of Science:
- Biochemistry
- Animal Physiology
- Evolutionary Biology
Background:
- The alternative oxidase (AOX) is found widely across the animal kingdom.
- Its precise physiological role in animals has remained largely unclear.
- Previous research suggests AOX involvement in stress resistance.
Purpose of the Study:
- To review current evidence on the physiological role of AOX in animals.
- To explore AOX's potential function in stress tolerance.
- To investigate the reasons for AOX loss in certain animal lineages.
Main Methods:
- Literature review of existing studies on AOX in animals.
- Analysis of data from model organisms regarding AOX expression and function.
- Comparative analysis of AOX presence and absence across different animal groups.
Main Results:
- Evidence suggests AOX may confer resistance to diverse stressors like toxins, hypoxia, nutrient deprivation, protein unfolding, desiccation, and pathogens.
- Unregulated expression of AOX in model organisms can mask its benefits and introduce stress.
- AOX has been lost in major groups including vertebrates, insects, and cephalopods.
Conclusions:
- AOX likely plays a significant role in animal stress resilience.
- The evolutionary loss of AOX in some taxa presents an intriguing question.
- Further experimental approaches are needed to elucidate AOX's function and evolutionary trajectory.
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