The Genome Strikes Back: The Evolutionary Importance of Defence Against Mobile Elements
Increasingly, we regard the genome as a site and source of genetic conflict. This fascinating ‘bottom-up’ view brings up appealing connections between genome biology and whole-organism ecology, in which populations of elements compete with one another in their genomic habitat. Unlike other habitats, though, a host genome has its own evolutionary interests and is often able to defend itself against molecular parasites. Most well-studied organisms employ strategies to protect their genomes against the harmful effects of genomic parasites, including methylation, various pathways of RNA interference, and more unusual tricks such as repeat induced point-mutation (RIP). These genome defence systems are not obscure biological curiosities, but fundamentally important to the integrity and cohesion of the genome, and exert a powerful influence on genome evolution.
KeywordsTransposable elements Intragenomic conflict Epigenetics Evolution of genetic systems
- Antonovics, J., & Abrams, J. (2004). Intratetrad mating and the evolution of linkage relationships. Evolution, 58(4), 72–709.Google Scholar
- Bergman, C. M., et al. (2006) Recurrent insertion and duplication generate networks of transposable element sequences in the Drosophila Melanogaster genome. Genome Biology, 7:R112. doi: 10.1186/Gb–2006–7–11–R112.
- Clark, J. B., & Kidwell, M. G. (1997). A phylogenetic perspective on P transposable element evolution in Drosophila. Proceedings of the National Academy of Sciences USA, 11428–11433.Google Scholar
- Josse, T., Teysset, L., et al. (2007). Telomeric trans-silencing: An epigenetic repression combining RNA silencing and heterochromatin formation. PLOS Genetics. doi: 10.1371/Journal.Pgen.0030158.Eor.