Goes Caio Augusto Gomes, Dos Santos Rodrigo Zeni, Aguiar Weidy Rozendo Clemente, Alves Dálete Cássia Vieira, Silva Duílio Mazzoni Zerbinato de Andrade, Foresti Fausto, Oliveira Claudio, Utsunomia Ricardo, Porto-Foresti Fabio
Laboratório de Genética de Peixes, Faculdade Estadual Paulista "Júlio de Mesquita Filho", Departamento de Ciências Biológicas, Faculdade de Ciências, Bauru, Brazil.
Instituto de Ciências Biológicas e da Saude, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil.
Front Genet. 2022 Jun 21;13:884072. doi: 10.3389/fgene.2022.884072. eCollection 2022.
Eukaryotic genomes are usually enriched in repetitive DNA sequences, which can be classified as dispersed or tandemly repeated elements. Satellite DNAs are noncoding monomeric sequences organized in a head-to-tail fashion that are generally located on the subtelomeric and/or pericentromeric heterochromatin. In general, a single species incorporates a diverse group of satellite DNA families, which collection is called satellitome. Here, we characterized three new satellitomes from distinct characid fish ( and ) using a combination of genomic, cytogenetic, and bioinformatic protocols. We also compared our data with the available satellitome of We described 57 satellite DNA (satDNA) families of (80 variants), 50 of (77 variants), and 33 of (54 variants). Our analyses demonstrated that several sequences were shared among the analyzed species, while some were restricted to two or three species. In total, we isolated 104 distinctive satDNA families present in the four species, of which 10 were shared among all four. Chromosome mapping revealed that the clustered satDNA was mainly located in the subtelomeric and pericentromeric areas. Although all species demonstrated the same pattern of clusterization of satDNA, the number of clusters per genome was variable, indicating a high dynamism of these sequences. In addition, our results expand the knowledge of the As51 satellite DNA family, revealing that and exhibited an abundant variant of 39 bp, while showed a variant of 43 bp. The majority of satDNAs in the satellitomes analyzed here presented a common library repetitive sequence in and , with abundance variations in each species, as expected for closely related groups. In addition, we concluded that the most abundant satDNA in (As51) passed through a diversification process in this group, resulting in new variants exclusive of .
真核生物基因组通常富含重复DNA序列，这些序列可分为分散重复元件或串联重复元件。卫星DNA是一种非编码单体序列，以头对尾的方式排列，通常位于亚端粒和/或着丝粒周围的异染色质上。一般来说，单个物种包含一组不同的卫星DNA家族，这些家族的集合称为卫星基因组。在这里，我们结合基因组学、细胞遗传学和生物信息学方法，对来自不同脂鲤科鱼类（和）的三个新卫星基因组进行了表征。我们还将我们的数据与现有的卫星基因组进行了比较。我们描述了（80个变体）的57个卫星DNA（satDNA）家族、（77个变体）的50个以及（54个变体）的33个。我们的分析表明，分析的物种之间共享了几个序列，而有些序列则仅限于两三个物种。我们总共分离出了这四个物种中存在的104个独特的satDNA家族，其中10个在所有四个物种中都有共享。染色体定位显示，成簇的satDNA主要位于亚端粒和着丝粒区域。尽管所有物种都表现出相同的satDNA聚类模式，但每个基因组中的聚类数量是可变的，这表明这些序列具有高度的动态性。此外，我们的结果扩展了对As51卫星DNA家族的认识，揭示了和表现出一个丰富的39 bp变体，而表现出一个43 bp的变体。在这里分析的卫星基因组中的大多数satDNA在和中呈现出一个共同的文库重复序列，每个物种中存在丰度差异，这对于密切相关的群体来说是预期的。此外，我们得出结论，中最丰富的satDNA（As51）在这个群体中经历了一个多样化过程，产生了特有的新变体。
