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On the origin of eukaryotic cytoskeleton
Matej Vesteg1, Juraj Krajcovic
1Institute of Cell Biology, Faculty of Natural Sciences, Comenius University, Mlynska dolina, 842 15 Bratislava, Slovakia. vesteg@fns.uniba.sk
Rivista Di Biologia
|July 5, 2008
Summary
The origin of eukaryotic cytoskeletal proteins may not be prokaryotic. These proteins might have evolved in pre-cells or via viruses before the emergence of eukaryotes.
Area of Science:
- Cell Biology
- Evolutionary Biology
- Origin of Life Studies
Background:
- The origin of eukaryotic-specific cytoskeletal proteins is intrinsically linked to the emergence of the domain Eukarya.
- The absence of these proteins in prokaryotes challenges conventional models suggesting a prokaryotic origin for the eukaryotic cytoskeleton.
Purpose of the Study:
- To investigate alternative origins for eukaryotic cytoskeletal proteins.
- To explore the potential role of pre-cellular entities and viruses in cytoskeletal evolution.
Main Methods:
- Comparative analysis of protein distribution across domains of life.
- Hypothetical modeling of pre-cellular and viral interactions.
- Review of existing evolutionary theories on eukaryogenesis.
Main Results:
- Eukaryotic cytoskeletal proteins may originate from pre-cellular populations co-existing with Bacteria and Archaea.
- The host cell (pre-karyote) for mitochondrial ancestors might have already possessed a eukaryotic-like cytoskeleton.
- Viruses are proposed as potential contributors, utilizing cytoskeletal proteins for genome management.
Conclusions:
- The prokaryotic origin of the eukaryotic cytoskeleton is questionable.
- Pre-cellular entities and viral elements offer plausible alternative sources for eukaryotic cytoskeletal proteins.
- This perspective reframes our understanding of early eukaryotic evolution.
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