Evolutionary dynamics of repetitive DNA and its impact on the genome diversification in the genus Sorghum

In this study, we in silico identified high-copy repeats and determined their chromosomal distribution to resolve the relationship and genome diversification of diploid S. bicolor and allotetraploid S. halepense accessions. The observed polymorphic distribution of the subtelomeric satellites being more abundant in the tetraploids indicates drastic genome rearrangements after the allopolyploidization event forming S. halepense. Application of a Sorghum-specific CENH3 antibody in combination with chromatin immunoprecipitation (ChIP) sequencing and fluorescence in situ hybridization (FISH) resulted in the identification of a centromere-specific satellite and evolutionarily conserved centromere-associated transposable elements. The impact of dynamic repetitive DNAs in the genome of the five related Sorghum genomes is discussed.