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Torres-Sabino, D.

Publications and source records attributed to Torres-Sabino, D..

3 recordsLinked to original sources

Striking olfactory receptor gene repertoire expansion in Senegalese sole (Solea senegalensis)

Chemoreception through olfaction is essential for regulating fish behaviour. Fish olfactory receptor repertoire comprises four multigene families (OlfC, OR, ORA and TAAR), whose diversity strongly shapes species-specific olfactory capabilities. In this study, the olfactory repertoire of the flatfish Solea senegalensis was characterized through orthology analysis with seven species, identifying 455 olfactory receptor genes in S. senegalensis, including large OlfC and TAAR gene expansions. Active functionality was shown in 426 genes of the total repertoire through the olfactory transcriptome and the RNA-seq libraries generated in this study, showing expression correlation within each family. Phylogenetic trees integrating orthologous and paralogous relationships, along with chromosomal locations were constructed. Notable synteny conservation was observed primarily among flatfish, partially lost with phylogenetically distant taxa. Olfactory receptor genes were heterogeneously distributed across twelve S. senegalensis chromosomes, constituting eleven major clusters of paralogous genes. Overall, S. senegalensis exhibits an expanded and specialized olfactory function, emerging as a promising model for studying chemoreception and addressing the reproductive issues in aquaculture.

evolutionary biology↗

Impaired Sertoli-Spermatogonia Interactions Contribute to Oligospermia and Infertility in F1 Captive-bred Male Solea senegalensis

Reproductive dysfunction of captive-bred males of the Senegalese sole (Solea senegalensis) represents a significant bottleneck for its aquaculture, as these fish exhibit reduced sperm production and impaired fertility compared to wild-bred counterparts acclimated to farm conditions. To elucidate the cellular and molecular mechanisms underlying this phenomenon, single-nuclei RNA sequencing was performed on gonadal tissue from adult captive-bred and wild-bred males. The analysis yielded a high-quality dataset comprising [~]80.000 cells, which were grouped into eleven distinct clusters representing all major germline and somatic cell types, including spermatogonial stem cells, differentiating spermatogonia, spermatocytes, spermatids, Sertoli cells, Leydig cells, immune cells, and peritubular myoid cells. It is noteworthy that captive-bred males exhibited a marked overrepresentation of proliferative spermatogonia and a significant reduction in mature spermatids, suggesting a disruption in the progression of spermatogenesis. Differential expression and functional enrichment analyses revealed that spermatogonial cells in captive-bred males displayed heightened translational activity alongside downregulation of pathways related to cell-cell communication and interaction. Focused cell-cell communication analyses further indicated defective Sertoli-spermatogonia interactions as a key factor contributing to oligospermia and infertility of captive-bred males. This study provides the first single-nuclei transcriptomic atlas of the Senegalese sole male gonad, offering valuable insights into the molecular basis of reproductive failure in captivity related to gonadal development. The findings of the study will inform future strategies to enhance selective breeding and improve aquaculture productivity for this economically important species.

genomics↗

Developmental landscape of shark telencephalon sheds light on the evolution of telencephalic cell types and the ancient origin of Cajal-Retzius cells

The emergence of predation and associated complex behaviors in jawed vertebrates (gnathostomes) were major driving forces in brain evolution. To gain insight into the neuronal complexity of the last common gnathostome ancestor, we studied the development of the shark telencephalon by combining single-cell and spatial transcriptomics. Our findings suggest an ancient origin of pallial neurogenesis, including basal progenitors, which were previously only identified in tetrapods. We find evidence for migrating gabaergic neurons populating the dorsal pallium, where we observe incipient layering. Finally, we provide evidence for the existence of Cajal-Retzius cells in the developing shark telencephalon, with a conserved molecular profile and tissue localization relative to mammals. Our analyses revealed that major features of the vertebrate pallium arose much earlier than previously thought, in the gnathostome lineage.

developmental biology↗