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Extensive retroviral diversity in shark
Guan-Zhu Han1,2
1Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, 210023, China. guanzhu@email.arizona.edu.
Retrovirology
|May 1, 2015
Summary
Researchers discovered diverse endogenous retroviruses (ERVs) in elephant sharks, revealing ancient retroviral associations with cartilaginous fishes and informing retrovirus evolution studies.
Area of Science:
- Virology
- Evolutionary Biology
- Genomics
Background:
- Retroviruses are widespread in vertebrates, but their diversity in basal vertebrates remains largely unexplored.
- Endogenous retroviruses (ERVs) offer insights into retroviral ecology and evolution.
Purpose of the Study:
- To investigate the diversity of endogenous retroviruses (ERVs) in the elephant shark (Callorhinchus milii).
- To understand the evolutionary history and diversity of retroviruses in basal vertebrates.
Main Methods:
- Genome-scale screening for endogenous retroviral elements in the elephant shark genome.
- Phylogenetic analysis of identified retroviral sequences.
Main Results:
- Identification of three complete or nearly complete ERVs and numerous ERV fragments, designated C. milli ERVs (CmiERVs).
- Phylogenetic analysis revealed three distinct lineages of CmiERVs.
- Estimated ancient genome invasions by these retroviruses occurring over 50 million years ago.
Conclusions:
- The study reveals significant retroviral diversity within the elephant shark.
- Diverse retroviruses have been associated with cartilaginous fishes for millions of years.
- These findings contribute to understanding the broader diversity and evolution of retroviruses.
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