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Evolution of the TSC1/TSC2-TOR signaling pathway.
Jaco Serfontein1, R Ellen R Nisbet, Christopher J Howe
1Cambridgeshire and Peterborough NHS Foundation Trust, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
Science Signaling
|July 1, 2010
Summary
The TSC1/TSC2-TOR pathway evolved gradually, not fully conserved in eukaryotes. Additional components like TSC1 and TSC2 were added later in specific lineages.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Cellular Biology
Background:
- The TSC1/TSC2-TOR signaling pathway regulates crucial cellular processes like protein synthesis.
- Previous research suggested this pathway was broadly conserved across eukaryotes.
Purpose of the Study:
- To investigate the evolutionary history of the TSC1/TSC2-TOR signaling pathway.
- To determine if the pathway is fully conserved throughout eukaryotic evolution.
Main Methods:
- Comparative analysis of complete eukaryotic genome sequences.
- Phylogenetic analysis of pathway components.
Main Results:
- The TSC1/TSC2-TOR pathway originated from a simpler ancestral pathway.
- Key components, TSC1 and TSC2, were acquired independently in specific eukaryotic lineages.
- The findings suggest a revised eukaryotic tree of life, grouping unikonts with Excavata and Chromalveolata.
Conclusions:
- The TSC1/TSC2-TOR pathway's evolution is more complex than previously thought, involving stepwise addition of components.
- This study reframes our understanding of eukaryotic evolution and the origins of key signaling pathways.
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