Natural GMOs Part 271. The Elephant. There is a virus derived gene in elephants

Highlights

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Endogenous adeno-associated virus elements derived from the rep gene were found in elephants.

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The elements (enAAV-rep) encoded a nearly intact open reading frame (ORF, gene candidate) of the rep gene.

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enAAV-rep was specifically expressed as mRNA in the liver in Asian elephant.

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Purifying selection has operated on the ORF at the amino acid sequence level.

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Elephant enAAV-rep may have been co-opted in the liver.

Abstract

An endogenous viral element derived from adeno-associated virus containing a nearly intact open reading frame (ORF, gene-candidate) of the rep gene (enAAV-rep) has been identified in the genomes of various mammals including degu and African elephant.

 Particularly, in degu, mRNA expression of enAAV-rep has been observed specifically in the liver. Here we newly identified enAAV-rep in Asian elephant and rock hyrax, both of which are afrotherians. The enAAV-rep of African and Asian elephants appeared to be orthologous and originated from an integration event of the entire genome of AAV into the ancestral genome of elephants more than 6 million years ago, whereas that of rock hyrax appeared to have originated independently. Negative selection operating at the amino acid sequence level was detected for the ORF of enAAV-rep in elephants. As in degu, mRNA expression of enAAV-rep was specifically observed in the liver in Asian elephant. Integrations of enAAV-rep appeared to have occurred independently on the evolutionary lineages of elephants and degu, suggesting that the AAV Rep protein has been co-opted repeatedly in the mammalian liver.

@ An endogenous adeno-associated virus element in elephants: