Repeatome Dynamics and Sex Chromosome Differentiation in the XY and XY1Y2 Systems of the Fish Hoplias malabaricus (Teleostei; Characiformes)
The wolf fish <i>Hoplias malabaricus</i> is a Neotropical species characterized by remarkable karyotypic diversity, including seven karyomorphs (KarA-G) with distinct sex chromosome systems. This study investigated the homologous XY (KarF) and XY<sub>1</sub>Y<sub>2</sub> (KarG) sex chromosome systems present in this species by integrating cytogenetics and genomics to examine sex chromosomes' composition through characterization of repeatome (satellite DNA and transposable elements) and sex-linked markers. Our analysis indicated that both karyomorphs are little differentiated in their sex chromosomes content revealed by satDNA mapping and putative sex-linked markers. Both repeatomes were mostly composed of transposable elements, but neither intra- (male versus female) nor interspecific (KarF x KarG) variations were found. In both systems, we demonstrated the occurrence of sex-specific sequences probably located on the non-recombining region of the Y chromosome supported by the accumulation of sex-specific haplotypes of HmfSat10-28/HmgSat31-28. This investigation offered valuable insights by highlighting the composition of homologous XY and XY<sub>1</sub>Y<sub>2</sub> multiple sex chromosomes. Although homologous, the large Y chromosome in KarF corresponds to two separate linkage groups (Y<sub>1</sub> and Y<sub>2</sub>) in KarG implying a specific meiotic arrangement involving the X chromosome in a meiotic trivalent chain. This scenario likely influenced recombination rates and, as a result, the genomic composition of these chromosomes.
Authors
- Jhon Alex Dziechciarz Vidal (ORCID: https://orcid.org/0000-0001-5779-0443)
- Fernando Henrique Santos de Souza (ORCID: https://orcid.org/0000-0001-6209-6296)
- Caio Augusto Gomes Goes (ORCID: https://orcid.org/0000-0002-7595-0014)
- Thomas Liehr (ORCID: https://orcid.org/0000-0003-1672-3054)
- Amanda Bueno da Silva (ORCID: https://orcid.org/0009-0004-3750-5122)
- Francisco de Menezes Cavalcante Sassi (ORCID: https://orcid.org/0000-0001-5699-5789)
- Fábio Porto‐Foresti (ORCID: https://orcid.org/0000-0001-8845-3845)
- Ricardo Utsunomia (ORCID: https://orcid.org/0000-0003-4565-6065)
- Tariq Ezaz (ORCID: https://orcid.org/0000-0003-4763-1347)
- Marcelo de Bello Cioffi (ORCID: https://orcid.org/0000-0003-4340-1464)
- Geize Aparecida Deon (ORCID: https://orcid.org/0000-0002-3374-2233)
- Mariannah Pravatti Barcellos de Oliveira
Institutions
- Universidade Federal de São Carlos (BR)
- University of Canberra (AU)
- Jena University Hospital (DE)
- Universidade Estadual Paulista (Unesp) (BR)
Publication Details
- Journal
- International Journal of Molecular Sciences
- Published
- 2025-06-24
- DOI
- https://doi.org/10.3390/ijms26136039
- Primary Topic
- Chromosomal and Genetic Variations
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Fundação de Amparo à Pesquisa do Estado de São Paulo
- Coordenação de Aperfeiçoamento de Pessoal de Nível Superior