Data from: Comparative analysis of DNA repeats and identification of novel Fesreba centromeric element in fescues and ryagrasses

Background Cultivated grasses are an important source of food for domestic
animals worldwide. Better knowledge of their genomes can speed up the
development of new cultivars with better quality and resistance to biotic
and abiotic stresses. The most widely grown grasses are tetraploid
ryegrass species ( Lolium spp.) and diploid and hexaploid fescue species
(Festuca spp.). In this work, we characterized repetitive DNA sequences
and their contribution to genome size in five fescue and two ryegrass
species, as well as one fescue and two ryegrass cultivars. Results Partial
genome sequences produced by Illumina technology were used for genome-wide
comparative analyses using RepeatExplorer pipeline. Retrotransposons were
found to be the most abundant repeat types in all seven grass species.
Athila element of Ty3/gypsy family showed the most striking differences in
copy number between fescues and ryegrasses. The sequence data enabled the
assembly of an LTR element Fesreba, which is highly enriched in
centromeric and (peri)centromeric regions in all species. A combination of
FISH with a probe specific to Fesreba element and immunostaining with
CENH3 antibody showed their colocalization and indicated a possible role
of Fesreba in centromere function. Conclusions Comparative repeatome
analysis in a set of fescues and ryegrasses provided new insights into
their genome organization and divergence, including the assembly of LTR
element Fesreba. A new LTR element Fesreba was identified and found
abundant in centromeric regions of the fescues and ryegrasses. It may have
a role in the function of their centromeres.