RESUMO
Introduction Eukaryotic genomes consist of both single and repetitive sequences, including Satellite DNAs (satDNA), which are non-coding sequences arranged in tandem arrays. These sequences play a crucial role in genomic functions and innovations, influencing processes such as nuclear material maintenance, heterochromatin formation, and sex chromosome differentiation. In this genomic era, advancements in next-generation sequencing and bioinformatic tools have facilitated the comprehensive cataloging of repetitive elements in genomes, particularly in non-model species. This study focuses on the satellitome of Ancistrus sp., a diverse fish species within the Loricariidae family. The genus Ancistrus displays significant karyotypic evolution, with deviations from the ancestral diploid number. Methods Using bioinformatic approaches, we identified 40 satellite DNA families in Ancistrus sp., constituting 5.19% of the genome. The abundance and divergence landscape analysis revealed diverse profiles, indicating recent amplification and homogenization of these satDNA sequences. Results The most abundant satellite, AnSat1-142, constitutes 2.1% of the genome, while the least abundant, AnSat40-52, represents 0.0034%. The monomer repeat length ranges from 16 to 142 base pairs, with an average length of 61 bp. These findings contribute to understanding the genomic dynamics and evolution of satDNAs in Ancistrus sp. Conclusion The study underscores the variability in satDNAs among fish species and provides valuable insights into the chromosomal organization and evolution of repetitive elements in non-model organisms.
RESUMO
Among the repetitive elements, satellite DNA (SatDNA) emerges as extensive arrays of highly similar tandemly repeated units, spanning megabases in length. Given that the satDNA PboSat01-176, previously characterized in P. boiei, prompted our interest for having a high abundance in P. boiei and potential for centromeric satellite, here, we employed various approaches, including low coverage genome sequencing, followed by computational analysis and chromosomal localization techniques in four Proceratophrys species and, investigating the genomic presence and sharing, as well as its potential for chromosomal centromere marker in Proceratophrys frog species. Our findings demonstrate that PboSat01-176 exhibits high abundance across all four Proceratophrys species, displaying distinct characteristics that establish it as the predominant repetitive DNA element in these species. The satellite DNA is prominently clustered in the peri/centromeric region of the chromosomes, particularly in the heterochromatic regions. The widespread presence of PboSat01-176 in closely related Proceratophrys species reinforces the validity of the library hypothesis for repetitive sequences. Thus, this study highlighted the utility of the satDNA family PboSat01-176 as a reliable centromeric marker in Proceratophrys species, with potential to be applied in other species of anuran amphibians. The observed sharing and maintenance of this sequence within the genus suggest possibilities for future research, particularly through expanded sampling to elucidate parameters that underlie the library hypothesis and the evolutionary dynamics of satDNA sequences.
