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Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
Published on: March 22, 2016
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Transmission, Evolution, and Endogenization: Lessons Learned from Recent Retroviral Invasions
Alex D Greenwood1, Yasuko Ishida2, Sean P O'Brien3
1Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research (IZW) in the Forschungsverbund Berlin e.V., Berlin, Germany.
Microbiology and Molecular Biology Reviews : MMBR
|December 15, 2017
Summary
Exogenous retroviruses (XRVs) can become endogenous retroviruses (ERVs) and vice versa. This review explores retroviral evolution, receptor usage, and koala retrovirus (KoRV) as a model for germ line invasion and XRV generation.
Area of Science:
- Virology and Evolutionary Biology
- Genomics and Bioinformatics
- Host-Pathogen Interactions
Background:
- Orthoretrovirinae subfamily viruses reverse transcribe RNA into DNA, integrating into host genomes.
- Exogenous retroviruses (XRVs) transmit horizontally, while endogenous retroviruses (ERVs) transmit vertically after germ line integration.
- ERVs can remain infectious, potentially generating new XRVs, blurring the lines between exogenous and endogenous forms.
Purpose of the Study:
- To integrate phylogenetic classifications and receptor identification to understand XRV and ERV origins and evolution.
- To explore the potential for ERVs to drive XRVs towards altered receptor usage.
- To examine the diverse evolutionary fates of retroviruses after endogenization, using koala retrovirus (KoRV) as a case study.
Main Methods:
- Review of recent phylogenetic classifications of retroviruses.
- Analysis of retroviral receptor identification studies.
- Integration of data on extant XRVs and endogenous retroviruses (ERVs), including fossil ERVs.
Main Results:
- Koala retrovirus (KoRV) provides insights into early germ line invasion and XRV generation from ERVs due to its heritable and infectious nature.
- Host biogeography and potential vectors like bats and rodents influence interspecies retroviral transmission.
- Studies of koalas and Australasian species reveal the evolutionary dynamics of retroviruses and host interactions.
Conclusions:
- Endogenization and exogenous transmission represent dynamic pathways in retroviral evolution.
- KoRV serves as a valuable model for understanding germ line invasion dynamics and the generation of infectious viruses from endogenous elements.
- Understanding retroviral evolution requires integrating phylogenetic, receptor, and biogeographical data, alongside studies of both extant and fossil retroviruses.
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