In Situ Gene Mapping of Two Genes Supports Independent Evolution of Sex Chromosomes in Cold-Adapted Antarctic Fish

• Published in: BioMed Research International
• Main Authors: Ghigliotti, Laura, Cheng, C. -H. Christina, Bonillo, Celine, Coutanceau, Jean-Pierre, Pisano, Eva
• Other Authors: Adaptation, Intégration, Réticulation et Evolution (AIRE), Evolution Paris Seine, Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre National de la Recherche Scientifique (CNRS), Italian National Programme for Antarctic Research (PNRA), L'Oreal-UNESCO program ``For Women in Science'' through the National Fellowship ``L'Oreal Italia Per le Donne e la Scienza'', NSF OPP
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SDV.BID]Life Sciences [q-bio]/Biodiversity; Antarctic; The ''Y''; Antarc*
• Online Access: https://hal.science/hal-01544911; https://doi.org/10.1155/2013/243938

International audience Two genes, that is, 5S ribosomal sequences and antifreeze glycoprotein (AFGP) genes, were mapped onto chromosomes of eight Antarctic notothenioid fish possessing a X1X1X2X2/X1X2Y sex chromosome system, namely, Chionodraco hamatus and Pagetopsis macropterus (family Channichthyidae), Trematomus hansoni, T. newnesi, T. nicolai, T. lepidorhinus, and Pagothenia borchgrevinki (family Nototheniidae), and Artedidraco skottsbergi (family Artedidraconidae). Through fluorescence in situ hybridization (FISH), we uncovered distinct differences in the gene content of the Y chromosomes in the eight species, with C. hamatus and P. macropterus standing out among others in bearing 5S rDNA and AFGP sequences on their Y chromosomes, respectively. Both genes were absent from the Y chromosomes of any analyzed species. The distinct patterns of Y and non-Y chromosome association of the 5S rDNA and AFGP genes in species representing different Antarctic fish families support an independent origin of the sex heterochromosomes in notothenioids with interesting implications for the evolutionary/adaptational history of these fishes living in a cold-stable environment.