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Tetracoding increases with body temperature in Lepidosauria.
Hervé Seligmann1, Antonieta Labra
1National Natural History Museum Collections, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel; Center for Ecological and Evolutionary Synthesis, Department of Bioscience, University of Oslo, Blindern, N-0316 Oslo, Norway; Department of Life Sciences, Ben Gurion University, 84105 Beer Sheva, Israel.
Bio Systems
|September 18, 2013
Summary
Expanded codons (tetracodons) may have aided early translation. This study confirms tetracoding increases with body temperature in Lepidosauria, supporting its role in high-temperature adaptation for protein synthesis.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Genomics
Background:
- Triplet codons may have been unstable for early translation without complex ribosomes.
- Expanded codons (tetracodons) are found in modern genomes and overlap with mitochondrial genes.
- Tetracoding is hypothesized to involve tRNAs with expanded anticodons and is GC-rich, suggesting high-temperature expression.
Purpose of the Study:
- To test the hypothesis that tetracoding is an adaptation to high temperatures.
- To investigate the relationship between mitochondrial tetracoding and body temperature in Lepidosauria.
Main Methods:
- Bioinformatic analysis of predicted mitochondrial tetracoding in Lepidosauria species.
- Comparison of tetracoding frequency with species' body temperatures.
- Confirmation of the association between expanded anticodon tRNAs and tetracoding.
Main Results:
- Mitochondrial tetracoding was predicted in Lepidosauria.
- Tetracoding frequency was found to increase with body temperature in Lepidosauria.
- The association between expanded anticodon tRNAs and tetracoding was confirmed in this group.
Conclusions:
- Tetracoding appears to be an adaptation for efficient translation at high temperatures.
- Tetracoding likely evolved to stabilize protein elongation when triplet codon-anticodon interactions are unstable due to heat.
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