These authors contributed equally to this work.
Adaptive eukaryote-to-eukaryote lateral gene transfer: stress-related genes of algal origin in the closest unicellular relatives of animals
Article first published online: 20 AUG 2008
© 2008 The Authors. Journal Compilation © 2008 European Society For Evolutionary Biology
Journal of Evolutionary Biology
Volume 21, Issue 6, pages 1852–1860, November 2008
How to Cite
NEDELCU, A. M., MILES, I. H., FAGIR, A. M. and KAROL, K. (2008), Adaptive eukaryote-to-eukaryote lateral gene transfer: stress-related genes of algal origin in the closest unicellular relatives of animals. Journal of Evolutionary Biology, 21: 1852–1860. doi: 10.1111/j.1420-9101.2008.01605.x
- Issue published online: 15 OCT 2008
- Article first published online: 20 AUG 2008
- Received 16 May 2008; revised 11 July 2008; accepted 15 July 2008
- ascorbate peroxidase;
- green algae;
- lateral gene transfer;
In addition to mutation, gene duplication and recombination, the transfer of genetic material between unrelated species is now regarded as a potentially significant player in the shaping of extant genomes and the evolution and diversification of life. Although this is probably true for prokaryotes, the extent of such genetic exchanges in eukaryotes (especially eukaryote-to-eukaryote transfers) is more controversial and the selective advantage and evolutionary impact of such events are less documented. A laterally transferred gene could either be added to the gene complement of the recipient or replace the recipient’s homologue; whereas gene replacements can be either adaptive or stochastic, gene additions are most likely adaptive. Here, we report the finding of four stress-related genes (two ascorbate peroxidase and two metacaspase genes) of algal origin in the closest unicellular relatives of animals, the choanoflagellates. At least three of these sequences represent additions to the choanoflagellate gene complement, which is consistent with these transfers being adaptive. We suggest that these laterally acquired sequences could have provided the primitive choanoflagellates with additional or more efficient means to cope with stress, especially in relation to adapting to freshwater environments and/or sessile or colonial lifestyles.