Satellite DNAs Unveil Clues about the Ancestry and Composition of B Chromosomes in Three Grasshopper Species

摘要: Supernumerary (B) chromosomes are dispensable genomic elements occurring frequently among grasshoppers. Most B enriched with repetitive DNAs, including satellite DNAs (satDNAs) that could be implicated in their evolution. Although studied some species, the specific ancestry of is difficult to ascertain and it was determined only a few examples. Here we used bioinformatics cytogenetics characterize composition putative three grasshopper Rhammatocerus brasiliensis, Schistocerca rubiginosa, Xyleus discoideus angulatus. Using RepeatExplorer pipeline searched for most abundant satDNAs Illumina sequenced reads, then generated probes fluorescent situ hybridization (FISH) determine chromosomal position. We this information infer events likely occurred at origin chromosomes. found twelve, nine, eighteen satDNA families genomes R. S. X. d. angulatus, respectively. Some revealed clustered organization on A varying number sites position along did not find chromosome. The shared support idea intraspecific from small autosomes i.e., pair S11 S9 S10 possibility involvement other pairs chromosome also hypothesized. Finally, discussed particular aspects composition, origin, evolution each species.