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Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Keys to eukaryality: planctomycetes and ancestral evolution of cellular complexity
John A Fuerst1, Evgeny Sagulenko
1School of Chemistry and Molecular Biosciences, The University of Queensland St Lucia, QLD, Australia.
Frontiers in Microbiology
|May 16, 2012
Summary
Planctomycetes exhibit complex cell structures, including a nucleus and endocytosis, suggesting a shared evolutionary past with eukaryotes. Evidence favors homology over convergent evolution for these eukaryote-like traits.
Area of Science:
- Cell Biology
- Evolutionary Biology
- Microbiology
Background:
- Planctomycetes possess internal membrane-bound compartments, a feature typically associated with eukaryotes.
- The planctomycete Gemmata obscuriglobus displays a double-membrane-bound nucleus and performs endocytosis.
- Understanding planctomycete cell structure is crucial for evaluating their evolutionary relationship with eukaryotes.
Purpose of the Study:
- To outline key planctomycete structural features relevant to eukaryote homology.
- To assess evidence for or against homology between Planctomycetes and eukaryotes.
- To evaluate evolutionary models for the origin of planctomycete cell organization.
Main Methods:
- Review and analysis of existing structural and molecular data on Planctomycetes.
- Consideration of evolutionary models, including reductive evolution from a proto-eukaryote-like ancestor.
- Evaluation of alternative hypotheses for the unique planctomycete cell plan.
Main Results:
- Planctomycetes exhibit eukaryote-like cellular complexity, including compartmentalization and endocytosis.
- Structural and molecular evidence supports a homologous relationship between Planctomycetes and eukaryotes.
- The findings are inconsistent with convergent evolution of these features in bacteria.
Conclusions:
- Planctomycetes share homologous features with eukaryotes, challenging traditional prokaryote-eukaryote distinctions.
- The data supports an evolutionary model involving reductive evolution from a complex ancestor.
- Planctomycetes offer insights into early eukaryote evolution and the origins of cellular complexity.
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