The majority of transcripts in the squid nervous system are extensively recoded by A-to-I RNA editing
- Tel Aviv University, Israel
- University of Connecticut Health Center, United States
- Bar-Ilan University, Israel
- University of Puerto Rico Medical Sciences Campus, Puerto Rico
Abstract
RNA editing by adenosine deamination alters genetic information from the genomic blueprint. When it recodes mRNAs, it gives organisms the option to express diverse, functionally distinct, protein isoforms. All eumetazoans, from cnidarians to humans, express RNA editing enzymes. However, transcriptome-wide screens have only uncovered about 25 transcripts harboring conserved recoding RNA editing sites in mammals and several hundred recoding sites in Drosophila. These studies on few established models have led to the general assumption that recoding by RNA editing is extremely rare. Here we employ a novel bioinformatic approach with extensive validation to show that the squid Doryteuthis pealeii recodes proteins by RNA editing to an unprecedented extent. We identify 57,108 recoding sites in the nervous system, affecting the majority of the proteins studied. Recoding is tissue-dependent, and enriched in genes with neuronal and cytoskeletal functions, suggesting it plays an important role in brain physiology.
Article and author information
Author details
Reviewing Editor
- Roderic Guigó, Center for Genomic Regulation, Spain
Ethics
Animal experimentation: Animal experimentation was conducted in accordance to the guidelines of the Marine Biological Laboratory in Woods Hole, Massachusetts.
Version history
- Received: October 15, 2014
- Accepted: January 8, 2015
- Accepted Manuscript published: January 8, 2015 (version 1)
- Version of Record published: February 4, 2015 (version 2)
Copyright
© 2015, Alon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The majority of transcripts in the squid nervous system are extensively recoded by A-to-I RNA editing
eLife 4:e05198.
https://doi.org/10.7554/eLife.05198
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