Fig. 4.

(a) Fosmid clones encompassing the relicts of the ancestral centromere (fosmid #32–34) and the repeat elements mapping to this genomic area. There are three α-satellite blocks: block A (red), block B (green), and block C (blue). The number of monomers is shown above each rectangle. The third block is actually made up of two separated units (a 12 bp interruption occurred inside the 68th monomer, as indicated by a light blue arrow). All the monomers are directly oriented except for the last 19 monomers of block C (the boundary is highlight by a purple arrow). (b) Dot matrix view showing regions of similarity (based upon the BLAST results) obtained after plotting self-comparison of the sequence harboring the relicts of the ancient centromere. The presence of inverted sequences was visually revealed by the creation of gray streaks running diagonally from top left to bottom right. Dotted purple lines show the boundary between directly oriented and inverted sequences.