unexpected inheritance multiple integrations of ancient bornavirus and ebolavirusmarburgvirus sequences in vertebrate genomes意想不到的继承古代bornavirus和ebolavirusmarburgvirus的多个集成在脊椎动物的基因组序列.pdf

Unexpected Inheritance: Multiple Integrations of Ancient Bornavirus and Ebolavirus/Marburgvirus Sequences in Vertebrate Genomes 1 1 2 Vladimir A. Belyi , Arnold J. Levine *, Anna Marie Skalka * 1 Simons Center for Systems Biology, Institute for Advanced Study, Princeton, New Jersey, United States of America, 2 Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America Abstract Vertebrate genomes contain numerous copies of retroviral sequences, acquired over the course of evolution. Until recently they were thought to be the only type of RNA viruses to be so represented, because integration of a DNA copy of their genome is required for their replication. In this study, an extensive sequence comparison was conducted in which 5,666 viral genes from all known non-retroviral families with single-stranded RNA genomes were matched against the germline genomes of 48 vertebrate species, to determine if such viruses could also contribute to the vertebrate genetic heritage. In 19 of the tested vertebrate species, we discovered as many as 80 high-confidence examples of genomic DNA sequences that appear to be derived, as long ago as 40 million years, from ancestral members of 4 currently circulating virus families with single strand RNA genomes. Surprisingly, almost all of the sequences are related to only two families in the Order Mononegavirales: the Bornaviruses and the Filoviruses, which cause lethal neurological disease and hemorrhagic fevers, respectively. Based on signature landmarks some, and perhaps all, of the endogenous virus-like DNA sequences appear to be LINE element-facilitated integrations derived from viral mRNAs. The integrations represent genes that encode viral nucleocapsid, RNA-dependen