Genomic architecture of Triops sex chromosomes

Sex chromosomes have evolved independently multiple times in animals and plants and it is thought that sexual conflict underlies their evolution. The European tadpole shrimp Triops cancriformis has a range of sexual systems including gonochorism (dioecy), self-fertilising hermaphroditism and androdioecy (where populations are made of self-fertilising hermaphrodites and males at low frequencies). A previous genome-wide association study using RADseq demonstrated that sex is genetically determined in Triops cancriformiswith a ZW sex determination system and a smaller non-recombining sex-linked region in the androdioecious than in the dioecious population (Mathers et al. 2015 Transition in sexual system and sex chromosome evolution in the tadpole shrimp Triops cancriformis Heredity 115: 37-46. DOI: 10.1038/hdy.2015.10). In this project, we produce genomic data (PacBio and MiSeq Illumina) for diocious, androdiocious and hermaphroditic populations of Triops. We carry out genome assemblies and annotation and identify sex-linked scaffolds to characterise sex chromosomes, sex-linked genes and putative master sex determination genes and differences in sex chromosome structure between populations with different sexual systems.