Isolation, characterization and chromosomal mapping of repeated DNA sequences in Abracris flavolineata (Acrididae, Ommatolampinae), with enphasis in the B chromosome analysis

Abstract

The repeated DNAs comprise a large fraction of eukaryotic genomes and are organized in distinct groups, primarily satellite DNAs, microsatellites, minissatellites, transposable elements (transposons and retrotransposons) and multigene families. These sequences have been useful in chromosomal analyses focused in studies of karyotypic diversification, structure and evolution of genomes and analyses of origin and diversification of sex and supernumerary chromosomes. The grasshoppers of the family Acrididae comprise the group with the highest diversity of Orthoptera order, being the subfamily Ommatolampinae represented by about 100 genera and 280 species. Chromosomal and genomic analyses focusing in repeated DNAs in this group are scarce, and in general restricted to the mapping of 18S ribosomal DNA. Other repetitive sequences, such as satellite DNAs, histone genes and 5S ribosomal DNA were performed only in European Acrididade species. In the present work it will be isolated and characterized repeated DNA elements, such multigene families and transposable elements in the species Abracris flavolineata, species that harbor a B chromosome. These analyses will allow a deep knowledge related to the genomic structure and evolutionary mechanism that act in the diversification of karyotypes and supernumerary chromosomes in grasshoppers. Moreover, the isolated sequences will be useful in future analyses using cytogenetic mapping in related species, contributing with the understanding of chromosomal/genomic diversification in neotropical Acridids. (AU)