Back to Search
Start Over
Evolution of a large ribosomal RNA multigene family in filamentous fungi: birth and death of a concerted evolution paradigm
- Source :
- Proceedings of the National Academy of Sciences of the United States of America. 102(14)
- Publication Year :
- 2005
-
Abstract
- In eukaryotes, the primary components of the ribosome are encoded by multicopy nuclear ribosomal RNA (rRNA) genes: 28/26S, 18S, 5.8S, and 5S. Copies of these genes are typically localized within tandem arrays and homogenized within a genome. As a result, nuclear rRNA gene families have become a paradigm of concerted evolution. In filamentous fungi of the subphylum Pezizomycotina, 5S rRNA genes exist as a large and dispersed multigene family, with between 50 and 100 copies per genome. To determine whether these genes defy the concerted evolution paradigm, we examined the patterns of evolution of these genes by using sequences from the complete genomes of four species. Analyses of these sequences revealed ( i ) multiple 5S gene types within a genome, ( ii ) interspecies clustering of gene types, ( iii ) multiple identical gene types shared among species, ( iv ) multiple pseudogenes within a genome, and ( v ) presence/absence variation of individual 5S copies in comparisons of closely related species. These results demonstrate that the 5S family in these species is characterized by birth-and-death evolution under strong purifying selection. Furthermore, our results suggest that birth-and-death evolution occurs at different rates in the genera examined, and that the multiplication and movement of 5S genes across the genome are highly dynamic. As such, we hypothesize that a mechanism resembling retroposition controls 5S rRNA gene amplification, dispersal, and integration in the genomes of filamentous fungi.
- Subjects :
- Genome evolution
Pseudogene
Genes, Fungal
Molecular Sequence Data
Gene Dosage
Biology
Genome
Aspergillus nidulans
Evolution, Molecular
5S ribosomal RNA
Fusarium
Gene family
Gene
Phylogeny
Genetics
Multidisciplinary
Concerted evolution
Neurospora crassa
Fungi
RNA, Fungal
Ribosomal RNA
Biological Sciences
Magnaporthe
RNA, Ribosomal
Multigene Family
Pseudogenes
Subjects
Details
- ISSN :
- 00278424
- Volume :
- 102
- Issue :
- 14
- Database :
- OpenAIRE
- Journal :
- Proceedings of the National Academy of Sciences of the United States of America
- Accession number :
- edsair.doi.dedup.....b6457a1f5ec4098443940717d71d7a41