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Published on: December 29, 2017
Evolution of the eukaryotic membrane-trafficking system: origin, tempo and mode
1Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK. jbd26@cam.ac.uk
Journal of Cell Science
|August 24, 2007
Summary
The eukaryotic endomembrane system likely originated from within the proto-eukaryote itself, evolving rapidly through gene duplication. This complex cellular machinery predates the last common eukaryotic ancestor (LCEA).
Area of Science:
- Cellular evolution
- Molecular biology
- Genomics
Background:
- The endomembrane system's emergence is key to eukaryote evolution.
- Prokaryotic origins for endomembrane components are less evident than for other organelles.
- Understanding membrane-trafficking machinery evolution is crucial.
Purpose of the Study:
- To investigate the evolutionary origins of the eukaryotic endomembrane system.
- To elucidate the mechanisms behind the development of membrane-trafficking machinery.
- To understand the timeline of endomembrane system evolution in early eukaryotes.
Main Methods:
- Genomic analyses
- Molecular evolutionary studies
- Comparative genomics
Main Results:
- Evidence suggests an autogenous origin for eukaryotic membrane-trafficking machinery.
- Early eukaryotic ancestors possessed a complex endomembrane system.
- Gene duplications and paralogous expansion significantly contributed to system complexity.
- The last common eukaryotic ancestor (LCEA) likely had a sophisticated trafficking system.
Conclusions:
- The eukaryotic endomembrane system evolved rapidly from a simple proto-eukaryotic precursor.
- Paralogous gene family expansion was a major driver of endomembrane system complexity.
- Subsequent modifications have led to diverse membrane-trafficking systems in extant eukaryotes.
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