Gatto Kaleb Pretto, Targueta Cintia Pelegrineti, Vittorazzi Stenio Eder, Lourenço Luciana Bolsoni
Laboratório de Estudos Cromossômicos, Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, Campinas 13083-863, São Paulo, Brazil.
Laboratório de Citogenética Evolutiva e Conservação Animal, Departamento de Genética, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba 80230-901, Paraná, Brazil.
Biomolecules. 2025 Jul 12;15(7):1001. doi: 10.3390/biom15071001.
Horizontal gene transfer (HGT), the non-Mendelian transfer of genetic material between organisms, is relatively frequent in prokaryotes, whereas its extent among eukaryotes remains unclear. Here, we raise the hypothesis of a possible cross-phylum HGT event involving 5S ribosomal DNA (rDNA). A specific type of 5S rDNA sequence from the anuran was highly similar to a 5S rDNA sequence of the genome of its flatworm parasite . A maximum likelihood analysis revealed phylogenetic incongruence between the gene tree and the species trees, as the 5S rDNA sequence from was grouped along with the sequences from the anurans. Sequence divergence analyses of the gene region and non-transcribed spacer also agree with an HGT event from to . Additionally, we examined whether contamination of the genome assembly with frog DNA could explain our findings but found no evidence to support this hypothesis. These findings highlight the possible contribution of HGT to the high diversity observed in the 5S rDNA family.
水平基因转移（HGT）是指生物体之间遗传物质的非孟德尔式转移，在原核生物中相对频繁，而其在真核生物中的程度仍不清楚。在这里，我们提出了一个涉及5S核糖体DNA（rDNA）的可能的跨门水平基因转移事件的假设。来自无尾两栖类动物的一种特定类型的5S rDNA序列与它的扁形虫寄生虫基因组的5S rDNA序列高度相似。最大似然分析揭示了基因树和物种树之间的系统发育不一致，因为来自寄生虫的5S rDNA序列与来自无尾两栖类动物的序列聚在一起。基因区域和非转录间隔区的序列分歧分析也支持从寄生虫到无尾两栖类动物的水平基因转移事件。此外，我们检查了寄生虫基因组组装中青蛙DNA的污染是否可以解释我们的发现，但没有发现支持这一假设的证据。这些发现突出了水平基因转移对5S rDNA家族中观察到的高度多样性的可能贡献。
