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 show that the cat archetypal satellite DNA sequence, 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-SAT-related 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 intermingling with 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.

An ancient satellite repeat controls gene expression and embryonic development inAedes aegyptithrough a highly conserved piRNA

“…This observation suggests that the locus evolved in the late Triassic after divergence of the Anophelinae from the Culicinae subfamily of mosquitoes (229-192 mya 33 ), but before further divergence of the culicine genera (226-172 mya 33 ). This establishes this repeat locus as one of the very few ancient and deeply conserved satellite repeats that have hitherto been described 28-30,34 . Conservation of the locus over million years of mosquito evolution strongly suggests important and conserved functions for the locus and its associated piRNAs.…”

Decoding the Role of Satellite DNA in Genome Architecture and Plasticity—An Evolutionary and Clinical Affair

“…Nevertheless, some satDNAs seem to have been preserved or "frozen" across different taxa during long evolutionary periods [22][23][24] with some of them being transcribed into satellite non-coding RNAs (satncRNAs). Indeed, transcripts of satDNAs have been reported in different species, highlighting a possible role for satncRNAs in the regulation of gene expression, cancer outcomes and aging [25][26][27].…”

Bovine satellite DNAs – a history of the evolution of complexity and its impact in the Bovidae family

“…In this repeat monomer, 12 highly conserved CpG sites were found (Kang et al 2001;Yamanaka et al 2011), and these seem to be highly methylated in most tissues (Schnedl et al 1976;Sturm & Taylor 1981;Pagés & Roizés 1982;Adams et al 1983). Additionally, it has been suggested that these satDNAs (like some others: Biscotti et al 2015;Chaves et al 2017) could be transcriptionally active (Su et al 1982), being transcribed by RNA polymerase III.…”

“…However, the systematic and phylogenetic relationships among the various species of this family are still under discussion (Rubes et al 2008;MacEachern et al 2009;Nieddu et al 2015). Nevertheless, the comparative study of the nucleotide sequences and locations of repetitive DNA families in related species is providing information about their own evolutionary mechanisms and the species' evolutionary history, since some repetitive sequences are extremely well conserved between species (Petraccioli et al 2015;Chaves et al 2017), while others are so variable that they can resolve taxonomic issues, defining differences between closely related species (Chaves et al 2000a(Chaves et al , 2005Adega et al 2006).…”

“…Several satDNA families of different origin are usually found in the genome of a species or a group of species, and these usually differ in the nucleotide sequence, monomer length, complexity, chromosomal location and/or abundance, as well as in their evolutionary history (Ugarkovic & Plohl 2002;Slamovits & Rossi 2002;Kuhn et al 2008Kuhn et al , 2011López-Flores & Garrido-Ramos 2012;Rojo et al 2015). SatDNA sequences are known for presenting a rapid generation and elimination in related species (Plohl et al 2008;Vourc'h & Biamonti 2011); however, some of these sequences seem to have been preserved, at least in a few copies, over long evolutionary periods in some genomes (Mravinac et al 2002(Mravinac et al , 2005Petraccioli et al 2015;Chaves et al 2017).…”