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Parallel evolution of amphioxus and vertebrate small-scale gene duplications
Marina Brasó-Vives1,2, Ferdinand Marlétaz3, Amina Echchiki4,5
1Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland. marina.brasovives@unil.ch.
Genome Biology
|November 19, 2022
Summary
Amphioxus, non-vertebrate chordates, show small-scale gene duplication histories similar to vertebrates, despite slower overall evolution. This suggests conserved mechanisms for gene duplication and functional specialization across chordate lineages.
Area of Science:
- Evolutionary Biology
- Genomics
- Developmental Biology
Background:
- Amphioxus (non-vertebrate chordates) exhibit slow morphological and molecular evolution.
- They share fundamental chordate body-plan and genome organization with vertebrates but lack 2R whole-genome duplications.
- Amphioxus serve as crucial outgroups for studying vertebrate genome evolution and Evolutionary Developmental Biology (Evo-Devo).
Purpose of the Study:
- To investigate the history of small-scale gene duplications in the amphioxus lineage.
- To compare amphioxus small-scale gene duplication history with that of vertebrates (both small- and large-scale).
Main Methods:
- Analysis of gene duplications in the European amphioxus (Branchiostoma lanceolatum) using a high-quality genome reference.
- Comparative analysis of gene duplication profiles, expression levels, and functional specialization between amphioxus and vertebrates.
- Examination of gene synteny conservation between two amphioxus species (B. lanceolatum and B. floridae).
Main Results:
- The amphioxus lineage displays a history of small-scale gene duplications comparable to vertebrates, despite its slow overall molecular evolution.
- Parallel gene duplication profiles and conserved functional constraints were observed between amphioxus and vertebrates.
- Amphioxus gene duplicates exhibit similar expression levels and functional specialization patterns to those in vertebrates.
- Strong gene synteny conservation was found between B. lanceolatum and B. floridae, with two major chromosomal rearrangements.
Conclusions:
- Amphioxus' small-scale gene duplication history mirrors that of the vertebrate lineage in both quantitative and functional aspects.
- This resemblance highlights conserved evolutionary processes in gene duplication across chordates, irrespective of whole-genome duplication events.
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