The Evolutionary Consequences of Transposon-Related Pericentromer Expansion in Melon
Alexiou, Konstantinos G.
Ramos-Onsins, Sebastián E.
Casacuberta, Josep M.
Abstract Transposable elements (TEs) are a major driver of plant genome evolution. A part from being a rich source of new genes and regulatory sequences, TEs can also affect plant genome evolution by modifying genome size and shaping chromosome structure. TEs tend to concentrate in heterochromatic pericentromeric regions and their proliferation may expand these regions. Here, we show that after the split of melon and cucumber, TEs have expanded the pericentromeric regions of melon chromosomes that, probably as a consequence, show a very low recombination frequency. In contrast, TEs have not proliferated to a high extent in cucumber, which has small TE-dense pericentromeric regions and shows a relatively constant recombination rate along chromosomes. These differences in chromosome structure also translate in differences in gene nucleotide diversity. Although gene nucleotide diversity is essentially constant along cucumber chromosomes, melon chromosomes show a bimodal pattern of genetic variability, with a gene-poor region where variability is negatively correlated with gene density. Interestingly, genes are not homogeneously distributed in melon, and the high variable low-recombining pericentromeric regions show a higher concentration of melon-specific genes whereas genes shared with cucumber and other plants are essentially found in gene-rich chromosomal arms. The results presented here suggest that melon pericentromeric regions may allow gene sequences to evolve more freely than in other chromosomal compartments which may allow new ORFs to arise and eventually be selected. These results show that TEs can drastically change the structure of chromosomes creating different chromosomal compartments imposing different constraints for gene evolution.
633 - Cultius i produccions
Oxford University Press
Is part of
Genome Biology and Evolution
Morata, Jordi, Marc Tormo, Konstantinos G Alexiou, Cristina Vives, Sebastián E Ramos-Onsins, Jordi Garcia-Mas, and Josep M Casacuberta. 2018. "The Evolutionary Consequences Of Transposon-Related Pericentromer Expansion In Melon". Genome Biology And Evolution 10 (6): 1584-1595. Oxford University Press (OUP). doi:10.1093/gbe/evy115.
Grant agreement number
MICINN/Programa Estatal de I+D+I orientada a los retos de la sociedad/AGL2013-43244-R/ES/OBTENCION, SELECCION Y INTRODUCCION DE VARIABILIDAD EN GENOMAS DE PLANTAS CULTIVADAS/
MICINN/Programa Estatal de I+D+I orientada a los retos de la sociedad/AGL2016-78992-R/ES/IMPACTO DE LOS TRANSPOSONES EN LA EVOLUCION DE LOS GENOMAS DE PLANTAS CULTIVADAS/TRANSCROP
MINECO/Programa Estatal de I+D+I orientada a los retos de la sociedad/AGL2015-64625-C2-1-R/ES/DISECCION GENETICA DE DOS CARACTERES DE INTERES AGRONOMICO EN MELON: RESISTENCIA A CUCUMBER MOSAIC VIRUS Y MADURACION CLIMATERICA DE FRUTO/RESMELORIP
Genòmica i Biotecnologia
This item appears in the following Collection(s)
- ARTICLES CIENTÍFICS 
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as http://creativecommons.org/licenses/by-nc/4.0/