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Updated: Jul 15, 2026
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In Vivo Biosensor Tracks Non-apoptotic Caspase Activity in Drosophila
Published on: November 27, 2016
Conserved function of caspase-8 in apoptosis during bony fish evolution
Shin-ichi Sakata1, Yilin Yan, Yutaka Satou
1Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan.
Gene
|April 27, 2007
Summary
We identified and characterized the zebrafish caspase-8 (casp8) gene, finding it has a similar structure and pro-apoptotic function to mammalian CASP8. This suggests the role of caspase-8 in apoptosis is conserved across vertebrates.
Area of Science:
- Molecular Biology
- Developmental Biology
- Evolutionary Biology
Background:
- Caspase-8 is crucial for apoptotic signaling in mammals.
- Understanding caspase-8 evolution provides insights into conserved biological pathways.
Purpose of the Study:
- To identify and characterize the zebrafish caspase-8 (casp8) gene.
- To investigate the functional conservation and evolutionary trajectory of caspase-8.
Main Methods:
- Genomic organization analysis and chromosome mapping of the zebrafish casp8 gene.
- Functional assessment of zebrafish Casp8 protein in mammalian cells.
- Analysis of casp8 expression patterns during zebrafish development.
Main Results:
- Zebrafish casp8 exhibits a genomic structure similar to mammalian orthologs, with 10 exons.
- Zebrafish Casp8 protein demonstrates pro-apoptotic activity and can mediate signals via Fas and TNF receptors in mammalian cells.
- casp8 shows maternal expression and is present throughout zebrafish embryogenesis and larval stages.
- Chromosomal mapping revealed a unique segregation of casp8, casp10-like, and cflar genes in zebrafish compared to other vertebrates.
Conclusions:
- Zebrafish casp8 is structurally and functionally analogous to mammalian CASP8.
- The essential role of caspase-8 in apoptotic signaling pathways has been conserved throughout vertebrate evolution for at least 450 million years.
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