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A Bioinformatics Pipeline for Investigating Molecular Evolution and Gene Expression using RNA-seq
Published on: May 28, 2021
Evolution and functional diversity of jellyfish opsins
Hiroshi Suga1, Volker Schmid, Walter J Gehring
1Department of Cell Biology, Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland.
Current Biology : CB
|December 28, 2007
Summary
The evolution of animal vision involved early divergence of ciliary and rhabdomeric photoreceptor cells (PRCs) and opsins before the Cnidaria-Bilateria split. Jellyfish opsin analysis supports this ancient evolutionary origin.
Area of Science:
- Evolutionary biology
- Molecular biology
- Zoology
Background:
- Cnidaria possess complex eyes using ciliary photoreceptor cells (c-PRCs), distinct from insect rhabdomeric photoreceptor cells (r-PRCs).
- Opsins, the light-sensitive proteins, are categorized into ciliary opsins (c-opsins) and rhabdomeric opsins (r-opsins), with distinct evolutionary histories.
- Previous research suggested divergence of c- and r-PRCs and opsins predates the split between deuterostomes and protostomes.
Purpose of the Study:
- To investigate the early evolution of animal photoreceptor cells (PRCs) and opsins.
- To characterize the first cnidarian opsins and determine their phylogenetic relationship to other opsin subfamilies.
- To explore the expression patterns of opsins in hydrozoan jellyfishes.
Main Methods:
- Investigated two hydrozoan jellyfish species.
- Performed molecular phylogenetic analysis of cloned jellyfish opsins alongside opsins from other species (hydra, sea anemone).
- Analyzed tissue- and stage-specific expression patterns of Cladonema opsins.
Main Results:
- Characterized 20 novel cnidarian opsins.
- Phylogenetic analysis revealed jellyfish opsins are most closely related to c-opsins, indicating divergence before the Cnidaria-Bilateria split.
- Observed distinct tissue- and stage-specific expression of Cladonema opsins, with expression in eyes and gonads.
Conclusions:
- The divergence of c-opsins and r-opsins predates the split between Cnidaria and Bilateria.
- Opsin expression in jellyfish eyes suggests a role in vision.
- Opsin expression in gonads indicates a role in light-controlled gamete release.
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