Fig. 6

Comparative analyses of TE composition between A and B chromosomes. a Comparison of repeat landscapes of TEs provide insights on their evolutionary history in both A genome and the micro B and macro B of A. mexicanus and A. correntinus. The X-axis shows the percent of TEs in the genome while Y-axis represents the Kimura distances that ranged from value 0, representing recent TE copies, to 50 for the old TE insertions. Black arrows indicate the recent wave of transpositions in the genome of Astyanax genus (black arrows point to transposition waves). The higher abundance of LTRs (green) and other retroelements (blue) in the B chromosome landscapes can also be observed. Green arrows point towards the difference between abundance of A and B chromosome LTRs. b. Donut charts show the comparison of repeat composition between the As and B. The outer and inner rings depict A and B chromosomes respectively. Again, the higher percentage of LTRs and retroelements confirm their relative abundance on the B as compared to A chromosomes. Noticeably, the simple repeats percentage was higher on the Bs. c. FISH of representative elements on metaphase chromosomes of A. mexicanus and A. correntinus with B chromosomes analyzed for the organization of Tc Mariner, Gypsy and Rex elements. A dispersed pattern among diverse chromosomes, including Bs, was observed. Magnified view of B chromosomes is shown with the presence of markings of corresponding elements. The abundant signals of these TEs are indicative of their copious nature in Astyanax genome and parallel with the landscapes analyses