RNA editing: a driving force for adaptive evolution?
Version of Record online: 25 AUG 2009
Copyright © 2009 Wiley Periodicals, Inc.
Volume 31, Issue 10, pages 1137–1145, October 2009
How to Cite
Gommans, W. M., Mullen, S. P. and Maas, S. (2009), RNA editing: a driving force for adaptive evolution?. Bioessays, 31: 1137–1145. doi: 10.1002/bies.200900045
- Issue online: 15 SEP 2009
- Version of Record online: 25 AUG 2009
- National Institutes of Health. Grant Number: NS057739
- phenotypic plasticity;
- RNA editing
Genetic variability is considered a key to the evolvability of species. The conversion of an adenosine (A) to inosine (I) in primary RNA transcripts can result in an amino acid change in the encoded protein, a change in secondary structure of the RNA, creation or destruction of a splice consensus site, or otherwise alter RNA fate. Substantial transcriptome and proteome variability is generated by A-to-I RNA editing through site-selective post-transcriptional recoding of single nucleotides. We posit that this epigenetic source of phenotypic variation is an unrecognized mechanism of adaptive evolution. The genetic variation introduced through editing occurs at low evolutionary cost since predominant production of the wild-type protein is retained. This property even allows exploration of sequence space that is inaccessible through mutation, leading to increased phenotypic plasticity and provides an evolutionary advantage for acclimatization as well as long-term adaptation. Furthermore, continuous probing for novel RNA editing sites throughout the transcriptome is an intrinsic property of the editing machinery and represents the molecular basis for increased adaptability. We propose that higher organisms have therefore evolved to systems with increasing RNA editing activity and, as a result, to more complex systems.