Faculty of Sciences, São Paulo State University (UNESP), Bauru 17033-360, SP, Brazil.
Institute of Biological Sciences and Health, Federal Rural University of Rio de Janeiro, Seropédica 23890-000, RJ, Brazil.
Genes (Basel). 2022 Dec 28;14(1):91. doi: 10.3390/genes14010091.
Satellite DNAs (satDNAs) are tandemly repeated sequences that are usually located on the heterochromatin, and the entire collection of satDNAs within a genome is called satellitome. Primarily, these sequences are not under selective pressure and evolve by concerted evolution, resulting in elevated rates of divergence between the satDNA profiles of reproductive isolated species/populations. Here, we characterized two additional satellitomes of Characiformes fish ( and ) that diverged approximately 30 million years ago, while still retaining conserved karyotype features. The results we obtained indicated that several satDNAs (50% of satellite sequences in and 43% in ) show levels of conservation between the analyzed species, in the nucleotide and chromosomal levels. We propose that long-life cycles and few genomic changes could slow down rates of satDNA differentiation.
卫星 DNA(satDNA)是串联重复序列,通常位于异染色质中,基因组中的所有 satDNA 被称为卫星组。这些序列主要不受选择压力的影响,通过协同进化进化,导致生殖隔离的物种/种群的 satDNA 图谱之间的分歧率升高。在这里,我们描述了大约 3000 万年前分化的两种额外的鲇形目鱼类( 和 )的卫星组,同时仍保留保守的核型特征。我们得到的结果表明,在核苷酸和染色体水平上,几种 satDNA( 在 和 中分别占卫星序列的 50%和 43%)在分析的物种之间表现出一定程度的保守性。我们提出,长生命周期和很少的基因组变化可能会减缓 satDNA 分化的速度。