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High-throughput Quantitative Real-time RT-PCR Assay for Determining Expression Profiles of Types I and III Interferon Subtypes
Published on: March 24, 2015
Structural conservation of interferon gamma among vertebrates
Ram Savan1, Sarangan Ravichandran, Jack R Collins
1Laboratory for Experimental Immunology, Cancer and Inflammation Program, Center of Cancer Research, National Cancer Institute at Frederick, Frederick, MD 21702, USA. savanr@mail.nih.gov
Cytokine & Growth Factor Reviews
|March 10, 2009
Summary
Interferon gamma (IFN-gamma) evolved over 450 million years ago, predating the tetrapod-fish split. This crucial immune molecule shows conserved structure and function across vertebrates, suggesting ancient immune responses.
Area of Science:
- Immunology
- Evolutionary Biology
- Genomics
Background:
- Interferon gamma (IFN-gamma) is a key regulator of T(H)1 immune responses and has been extensively studied in mammals.
- Recent discoveries have identified IFN-gamma in avian and piscine species, prompting further evolutionary investigation.
Purpose of the Study:
- To construct an evolutionary history of IFN-gamma.
- To investigate the evolutionary origins and adaptations of IFN-gamma across vertebrate species.
- To analyze the conservation of regulatory elements and structural features of IFN-gamma.
Main Methods:
- Phylogenetic analysis of identified IFN-gamma DNA sequences.
- Comparative genomic analysis of IFN-gamma, IL-22, and IL-26 loci.
- Comparative structural modeling of IFN-gamma across species.
Main Results:
- IFN-gamma evolution predates the tetrapod-fish split, originating over 450 million years ago.
- A gene duplication event in teleosts suggests specific evolutionary adaptations in fish.
- Genomic loci and regulatory elements show conservation, with a disease-associated microsatellite in the first intron.
- Comparative modeling reveals conserved structural features despite interspecies differences.
Conclusions:
- The ancient origin and conserved nature of IFN-gamma suggest the presence of innate and adaptive T(H)1-like immune responses in lower vertebrates.
- IFN-gamma's evolutionary trajectory highlights its fundamental role in vertebrate immunity.
- The study provides insights into the deep evolutionary roots of adaptive immunity.
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