RNA Editing pp 149-162 | Cite as

ALU A-to-I RNA Editing: Millions of Sites and Many Open Questions

Part of the Methods in Molecular Biology book series (MIMB, volume 2181)


Alu elements are repetitive short interspersed elements prevalent in the primate genome. These repeats account for over 10% of the genome with more than a million highly similar copies. A direct outcome of this is an enrichment in long structures of stable dsRNA, which are the target of adenosine deaminases acting on RNAs (ADARs), the enzymes catalyzing A-to-I RNA editing. Indeed, A-to-I editing by ADARs is extremely abundant in primates: over a hundred million editing sites exist in their genomes. However, despite the radical increase in ADAR targets brought on by the introduction of Alu elements, the few evolutionary conserved editing sites manage to retain their editing levels. Here, we review and discuss the cost of having an unusual amount of dsRNA and editing in the transcriptome, as well as the opportunities it presents, which possibly contributed to accelerating primate evolution.

Key words

RNA editing Alu ADAR 



EYL was supported by the International Collaboration Grant from the Jacki and Bruce Barron Cancer Research Scholars’ Program, a partnership of the Israel Cancer Research Fund and City of Hope, as supported by The Harvey L. Miller Family Foundation [grant number 205467].


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Authors and Affiliations

  1. 1.Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan UniversityRamat GanIsrael

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