Sex chromosome and sex locus characterization in goldfish, Carassius auratus (Linnaeus, 1758)

BMC Genomics

Manfred Schartl¹  Yann Guiguen²  Amaury Herpin²  Elodie Jouanno²  Qiaowei Pan²  Romain Feron²  Justine Guguin²  John H. Postlethwait³  Yoshihiro Omori⁴  Laurent Journot⁵  Hugues Parrinello⁵  Christophe Klopp⁶  Cedric Cabau⁷  Margot Zahm⁷  Ming Wen⁸  Shawn M. Burgess⁹ 

[1] Developmental Biochemistry, Biozentrum, University of Würzburg;INRAE, LPGP;Institute of Neuroscience, University of Oregon;Laboratory of Functional Genomics, Graduate School of Bioscience, Nagahama Institute of Bioscience and Technology;Montpellier GenomiX (MGX), c/o Institut de Génomique Fonctionnelle;Plate-forme bio-informatique Genotoul, Mathématiques et Informatique Appliquées de Toulouse, INRAE;SIGENAE, GenPhySE, Université de Toulouse, INRAE, ENVT;State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Science, Hunan Normal University;Translational and Functional Genomics Branch, National Human Genome Research Institute;

关键词: Goldfish;    RADseq;    Poolseq;    Sex determination;    Sex markers;    Male genome assembly;   

DOI  :  10.1186/s12864-020-06959-3

来源: DOAJ

【 摘 要 】

Abstract Background Goldfish is an important model for various areas of research, including neural development and behavior and a species of significant importance in aquaculture, especially as an ornamental species. It has a male heterogametic (XX/XY) sex determination system that relies on both genetic and environmental factors, with high temperatures being able to produce female-to-male sex reversal. Little, however, is currently known on the molecular basis of genetic sex determination in this important cyprinid model. Here we used sequencing approaches to better characterize sex determination and sex-chromosomes in an experimental strain of goldfish. Results Our results confirmed that sex determination in goldfish is a mix of environmental and genetic factors and that its sex determination system is male heterogametic (XX/XY). Using reduced representation (RAD-seq) and whole genome (pool-seq) approaches, we characterized sex-linked polymorphisms and developed male specific genetic markers. These male specific markers were used to distinguish sex-reversed XX neomales from XY males and to demonstrate that XX female-to-male sex reversal could even occur at a relatively low rearing temperature (18 °C), for which sex reversal has been previously shown to be close to zero. We also characterized a relatively large non-recombining region (~ 11.7 Mb) on goldfish linkage group 22 (LG22) that contained a high-density of male-biased genetic polymorphisms. This large LG22 region harbors 373 genes, including a single candidate as a potential master sex gene, i.e., the anti-Mullerian hormone gene (amh). However, no sex-linked polymorphisms were detected in the coding DNA sequence of the goldfish amh gene. Conclusions These results show that our goldfish strain has a relatively large sex locus on LG22, which is likely the Y chromosome of this experimental population. The presence of a few XX males even at low temperature also suggests that other environmental factors in addition to temperature could trigger female-to-male sex reversal. Finally, we also developed sex-linked genetic markers, which will be important tools for future research on sex determination in our experimental goldfish population. However, additional work would be needed to explore whether this sex locus is conserved in other populations of goldfish.

【 授权许可】

Unknown