Cabral-de-Mello Diogo C, Zrzavá Magda, Kubíčková Svatava, Rendón Pedro, Marec František
Departamento de Biologia Geral e Aplicada, Instituto de Biociências/IB, UNESP-Univ Estadual Paulista, Rio Claro, Brazil.
Biology Centre, Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czechia.
Front Genet. 2021 Mar 30;12:661417. doi: 10.3389/fgene.2021.661417. eCollection 2021.
Tandem repeats are important parts of eukaryotic genomes being crucial e.g., for centromere and telomere function and chromatin modulation. In Lepidoptera, knowledge of tandem repeats is very limited despite the growing number of sequenced genomes. Here we introduce seven new satellite DNAs (satDNAs), which more than doubles the number of currently known lepidopteran satDNAs. The satDNAs were identified in genomes of three species of Crambidae moths, namely , , and , using graph-based computational pipeline RepeatExplorer. These repeats varied in their abundance and showed high variability within and between species, although some degree of conservation was noted. The satDNAs showed a scattered distribution, often on both autosomes and sex chromosomes, with the exception of both satellites in , in which the satDNAs were located at a single autosomal locus. Three satDNAs were abundant on the W chromosomes of and , thus contributing to their differentiation from the Z chromosomes. To provide background for the localization of the satDNAs, we performed a detailed cytogenetic analysis of the karyotypes of all three species. This comparative analysis revealed differences in chromosome number, number and location of rDNA clusters, and molecular differentiation of sex chromosomes.
串联重复序列是真核生物基因组的重要组成部分,例如对于着丝粒和端粒功能以及染色质调控至关重要。在鳞翅目中,尽管测序基因组的数量不断增加,但关于串联重复序列的知识仍然非常有限。在这里,我们介绍了七种新的卫星DNA(satDNA),这使目前已知的鳞翅目satDNA数量增加了一倍多。使用基于图形的计算管道RepeatExplorer,在三种夜蛾科蛾类的基因组中鉴定出了这些satDNA,即[具体蛾类物种1]、[具体蛾类物种2]和[具体蛾类物种3]。这些重复序列在丰度上有所不同,并且在物种内部和物种之间表现出高度变异性,尽管也注意到了一定程度的保守性。satDNA呈现出分散分布,通常在常染色体和性染色体上都有,[具体蛾类物种4]中的两种卫星DNA除外,它们位于单个常染色体位点。三种satDNA在[具体蛾类物种5]和[具体蛾类物种6]的W染色体上丰富,从而促进了它们与Z染色体的分化。为了为satDNA的定位提供背景信息,我们对所有三个物种的核型进行了详细的细胞遗传学分析。这种比较分析揭示了染色体数量、rDNA簇的数量和位置以及性染色体的分子分化方面的差异。