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07:04
Genotyping of Sea Anemone during Early Development
Published on: May 13, 2019
Multiple dicer genes in the early-diverging metazoa
Danielle de Jong1, Michael Eitel, Wolfgang Jakob
1Tieraerztliche Hochschule, Division of Ecology and Evolution, Hannover, Germany.
Molecular Biology and Evolution
|March 12, 2009
Summary
Investigating Dicer proteins in early-branching metazoans reveals striking gene diversity. Multiple Dicer genes in basal phyla suggest lineage-specific duplications and ancient evolutionary events, contrasting with higher metazoans.
Area of Science:
- Evolutionary Biology
- Molecular Biology
- Genomics
Background:
- Dicer proteins are crucial for RNA interference across diverse organisms.
- Previous studies focused on Dicer complements in "higher" metazoans.
- Early-branching metazoans lack comprehensive Dicer protein characterization.
Purpose of the Study:
- To characterize Dicer gene families in early-branching metazoans.
- To investigate the evolutionary history of Dicer proteins.
- To formulate hypotheses on Dicer functions in basal metazoans.
Main Methods:
- Cloning of partial cDNAs for Dicer genes from Nematostella vectensis and Placozoa.
- Identification of Dicer genes in Hydra magnipapillata and Amphimedon queenslandica using public databases.
- Phylogenetic analyses of metazoan Dicer proteins.
Main Results:
- Two Dicer genes found in cnidarians; five in Porifera and Placozoa.
- Phylogenetic analyses suggest an ancient "Proto-Dicer" gene duplication.
- Placozoa uniquely possesses representatives of this ancient duplication alongside lineage-specific duplications.
Conclusions:
- Basal metazoan phyla exhibit significant Dicer gene diversity, unlike most higher metazoans.
- Multiple Dicer genes in basal phyla likely arose from lineage-specific duplications.
- The diversity may indicate specialized functions, potentially in immune defense, in early metazoans.
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