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Mitonuclear dynamics in unisexual vertebrates
Randy L Klabacka1,2, Geoffrey E Hill3, Damian K Dowling4
1Department of Biology, Brigham Young University, Provo, UT, USA.
Summary
Unisexual vertebrates offer insights into mitochondrial evolution due to their unique hybrid and clonal nature. Their mitonuclear incompatibilities may limit lineage longevity, suggesting a
Area of Science:
- Evolutionary biology
- Genetics
- Mitochondrial genomics
Background:
- Sex and mitochondria are closely linked, complicated by mitochondria's uniparental inheritance and sexual reproduction's biparental inheritance.
- Unisexual vertebrate lineages, arising from hybridization and asexual reproduction, provide a model to study mitochondrial evolution without sex-related confounding factors.
Purpose of the Study:
- To explore mitonuclear genomic interactions in unisexual vertebrates.
- To understand the implications of these interactions on mitochondrial function, organismal performance, and fitness.
- To propose the 'Mitonuclear Erosion Hypothesis' explaining potential lineage limitations.
Main Methods:
- Reviewing existing literature and proposing multidisciplinary strategies.
- Disentangling the effects of clonality and hybridity.
- Quantifying contributions to mitochondrial function, organismal performance, and fitness.
Main Results:
- Unisexual vertebrates present a distinct genetic environment shaped by hybridity and clonality.
- Mitonuclear incompatibilities may arise from hybridity or clonality.
- These incompatibilities could increase extinction probability over time.
Conclusions:
- Unisexual vertebrates may be restricted to younger lineages due to mitonuclear incompatibilities.
- The 'Mitonuclear Erosion Hypothesis' suggests a mechanism for extinction in these lineages.
- Further research is needed to disentangle clonality and hybridity effects on mitochondrial dynamics and fitness.
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