Pogo-like transposases have been repeatedly domesticated into CENP-B-related proteins.
Bottom Line: Among the different centromere-associated proteins (CENP) identified, CENP-B has been independently domesticated from a pogo-like transposase twice: Once in mammals and once in fission yeast.Our results showed that CENP-B related genes are not restricted to holocentric insects.Our results highlight the importance of transposable elements as raw material for the recurrent evolution of important cellular functions.
Affiliation: Institute of Evolutionary Biology (CSIC- Universitat Pompeu Fabra), Barcelona, Spain.Show MeSH
Mentions: We constructed a phylogenetic tree to find out where insect CENP-B homologs are located in the previously published phylogeny containing a representative set of pogo transposases and pogo-derived genes (Casola et al. 2008). Phylogenetic trees of the full sequence set containing nonmetazoan transposases and transposase-derived genes can be found in supplementary figures S2 and S3, Supplementary Material online (see Materials and Methods). Our tree recovers the two monophyletic clades in metazoans: CR and Jerky related (JR) (fig. 3). CAG is located in the CR clade, and as expected, its closest transposase is the D. melanogaster pogo. The closest non-Drosophila CAG homolog is Tribolium castaneum TC005011. Most of the other insect CENP-B homolog genes, including the already described S. frugiperda and H. armigera CENP-B homologs, also fell in the CR clade. Insect and mammalian CR proteins form subclades inside the CR clade (fig. 3). Other than between D. melanogaster_CAG and D. ananassae_GF13390 transposase-derived genes, synteny is also conserved among Sfru_72F01, Harmi_94B11_25, and Bombyx_ BGIBMGA013624 suggesting that at least two additional independent exaptations, besides the mammal and fission yeast exaptations reported by Casola et al (2008), have occurred.Fig. 3.—
Affiliation: Institute of Evolutionary Biology (CSIC- Universitat Pompeu Fabra), Barcelona, Spain.