Widespread Endogenization of Densoviruses and Parvoviruses in Animal and Human Genomes

College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, People's Republic of China.
Journal of Virology (Impact Factor: 4.44). 07/2011; 85(19):9863-76. DOI: 10.1128/JVI.00828-11
Source: PubMed


Parvoviruses infect humans and a broad range of animals, from mammals to crustaceans, and generally are associated with a
variety of acute and chronic diseases. However, many others cause persistent infections and are not known to be associated
with any disease. Viral persistence is likely related to the ability to integrate into the chromosomal DNA and to establish
a latent infection. However, there is little evidence for genome integration of parvoviral DNA except for Adeno-associated virus (AAV). Here we performed a systematic search for homologs of parvoviral proteins in publicly available eukaryotic genome
databases followed by experimental verification and phylogenetic analysis. We conclude that parvoviruses have frequently invaded
the germ lines of diverse animal species, including mammals, fishes, birds, tunicates, arthropods, and flatworms. The identification
of orthologous endogenous parvovirus sequences in the genomes of humans and other mammals suggests that parvoviruses have
coexisted with mammals for at least 98 million years. Furthermore, some of the endogenized parvoviral genes were expressed
in eukaryotic organisms, suggesting that these viral genes are also functional in the host genomes. Our findings may provide
novel insights into parvovirus biology, host interactions, and evolution.

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Article: Widespread Endogenization of Densoviruses and Parvoviruses in Animal and Human Genomes

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