Marková Anna, Orosová Martina, Mora Pablo, Benovics Michal, Lorite Pedro
Institute of Parasitology, Slovak Academy of Sciences, Hlinkova 3, 040 01, Košice, Slovakia.
Department of Zoology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15, Bratislava, Slovakia.
Sci Rep. 2025 Jan 23;15(1):2945. doi: 10.1038/s41598-025-85728-2.
Acanthocephalan parasites are often overlooked in many areas of research, and satellitome and cytogenetic analyzes are no exception. The species of the genus Acanthocephalus are known for their very small chromosomes with ambiguous morphology, which makes karyotyping difficult. In this study, we performed the first satellitome analysis of three Acanthocephalus species to identify species- and chromosome-specific satellites that could serve as cytogenetic markers. RepeatExplorer2 revealed a remarkably high number of species-specific repeats, with a predominance of satellite DNAs, alongside variations in repetitive content between sexes. Five satellites in A. anguillae, two in A. lucii and six in A. ranae were successfully mapped to chromosomes using FISH. Each satellite showed a clustered hybridization signal at specific chromosomal locations, which allowed us to create a schematic representation of the distribution of satellites for each species. These newly identified satellites proved to be useful chromosomal markers for the accurate identification of homologous chromosome pairs. No FISH-positive signals were observed on the supernumerary chromosomes of A. anguillae and A. lucii, supporting the hypothesis that these chromosomes have recent origin.
棘头虫寄生虫在许多研究领域常常被忽视，卫星基因组和细胞遗传学分析也不例外。棘头虫属的物种以其染色体非常小且形态模糊而闻名，这使得核型分析变得困难。在本研究中，我们对三种棘头虫属物种进行了首次卫星基因组分析，以鉴定可作为细胞遗传学标记的物种特异性和染色体特异性卫星序列。RepeatExplorer2揭示了大量物种特异性重复序列，其中卫星DNA占主导地位，同时两性之间的重复内容也存在差异。使用荧光原位杂交（FISH）技术，将鳗鲡棘头虫的5个卫星序列、鲁氏棘头虫的2个卫星序列和蛙棘头虫的6个卫星序列成功定位到染色体上。每个卫星序列在特定的染色体位置显示出聚集的杂交信号，这使我们能够为每个物种创建卫星序列分布的示意图。这些新鉴定的卫星序列被证明是用于准确识别同源染色体对的有用染色体标记。在鳗鲡棘头虫和鲁氏棘头虫的超数染色体上未观察到FISH阳性信号，这支持了这些染色体起源较新的假说。
