Schematic overview of the centromeric rearrangements in centromeres 2 (A) and 3 (B) Arrowheads indicate rDNA palindrome sequences. The arrowhead direction gives the sequence direction from center to end of the rDNA palindrome. The rDNA palindrome sequence represented as empty arrowhead is only supported by theoretical evidence. Light gray line: unique chromosome sequence. The diagonal streaked rectangles depict the regions occupied by DIRS elements.