Skip to Main content Skip to Navigation
Journal articles

Dynamic evolution of megasatellites in yeasts.

Abstract : Megasatellites are a new family of long tandem repeats, recently discovered in the yeast Candida glabrata. Compared to shorter tandem repeats, such as minisatellites, megasatellite motifs range in size from 135 to more than 300 bp, and allow calculation of evolutionary distances between individual motifs. Using divergence based on nucleotide substitutions among similar motifs, we determined the smallest distance between two motifs, allowing their subsequent clustering. Motifs belonging to the same cluster are recurrently found in different megasatellites located on different chromosomes, showing transfer of genetic information between megasatellites. In comparison, evolution of the few similar tandem repeats in Saccharomyces cerevisiae FLO genes mainly involves subtelomeric homologous recombination. We estimated selective constraints acting on megasatellite motifs and their host genes, and found that motifs are under strong purifying selection. Surprisingly, motifs inserted within pseudogenes are also under purifying selection, whereas the pseudogenes themselves evolve neutrally. We propose that megasatellite motifs propagate by a combination of three different molecular mechanisms: (i) gene duplication, (ii) ectopic homologous recombination and (iii) transfer of motifs from one megasatellite to another one. These mechanisms actively cooperate to create new megasatellites, that may play an important role in the adaptation of Candida glabrata to its human host.
Complete list of metadatas

Cited literature [30 references]  Display  Hide  Download

https://hal-pasteur.archives-ouvertes.fr/pasteur-01370686
Contributor : Guy-Franck Richard <>
Submitted on : Friday, September 23, 2016 - 10:57:38 AM
Last modification on : Monday, June 15, 2020 - 3:10:40 PM

File

2010-Rolland et al.pdf
Publication funded by an institution

Licence


Distributed under a Creative Commons Attribution - NonCommercial 4.0 International License

Identifiers

Collections

Citation

Thomas Rolland, Bernard Dujon, Guy-Franck Richard. Dynamic evolution of megasatellites in yeasts.. Nucleic Acids Research, Oxford University Press, 2010, 38 (14), pp.4731-9. ⟨10.1093/nar/gkq207⟩. ⟨pasteur-01370686⟩

Share

Metrics

Record views

378

Files downloads

421