Small-scale gene duplications played a major role in the recent evolution of wheat chromosome 3B.
Genome Biol
; 16: 188, 2015 Sep 09.
Article
em En
| MEDLINE
| ID: mdl-26353816
ABSTRACT
BACKGROUND:
Bread wheat is not only an important crop, but its large (17 Gb), highly repetitive, and hexaploid genome makes it a good model to study the organization and evolution of complex genomes. Recently, we produced a high quality reference sequence of wheat chromosome 3B (774 Mb), which provides an excellent opportunity to study the evolutionary dynamics of a large and polyploid genome, specifically the impact of single gene duplications.RESULTS:
We find that 27 % of the 3B predicted genes are non-syntenic with the orthologous chromosomes of Brachypodium distachyon, Oryza sativa, and Sorghum bicolor, whereas, by applying the same criteria, non-syntenic genes represent on average only 10 % of the predicted genes in these three model grasses. These non-syntenic genes on 3B have high sequence similarity to at least one other gene in the wheat genome, indicating that hexaploid wheat has undergone massive small-scale interchromosomal gene duplications compared to other grasses. Insertions of non-syntenic genes occurred at a similar rate along the chromosome, but these genes tend to be retained at a higher frequency in the distal, recombinogenic regions. The ratio of non-synonymous to synonymous substitution rates showed a more relaxed selection pressure for non-syntenic genes compared to syntenic genes, and gene ontology analysis indicated that non-syntenic genes may be enriched in functions involved in disease resistance.CONCLUSION:
Our results highlight the major impact of single gene duplications on the wheat gene complement and confirm the accelerated evolution of the Triticeae lineage among grasses.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Triticum
/
Genes de Plantas
/
Evolução Molecular
/
Duplicação Gênica
/
Cromossomos de Plantas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Genome Biol
Assunto da revista:
BIOLOGIA MOLECULAR
/
GENETICA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
França