FA-SAT is an old satellite DNA frozen in several bilateria genomes

Abstract

In recent years, a growing body of evidence has recognized the tandem repeat sequences, and specifically satellite DNA, as a functional class of sequences in the genomic "dark matter." Using an original, complementary, and thus an eclectic experimental design, we showthat the cat archetypal satelliteDNAsequence, FA-SAT, is "frozen" conservatively in several Bilateria genomes.We found different genomic FA-SAT architectures, and the interspersion pattern was conserved. In Carnivora genomes, the FA-SATrelated sequences are also amplified, with the predominance of a specific FA-SAT variant, at the heterochromatic regions. We inspected the cat genome project to locate FA-SAT array flanking regions and revealed an intensive interminglingwith transposable elements. Our results also show that FA-SAT-related sequences are transcribed and that the most abundant FA-SAT variant is not always the most transcribed. We thus conclude that the DNA sequences of FA-SAT and their transcripts are "frozen" in these genomes. Future work is needed to disclose any putative function that these sequences may play in these genomes.