Chromosome-Level Genome Reveals the Origin of Neo-Y Chromosome in the Male Barred Knifejaw Oplegnathus fasciatus

摘要

The barred knifejaw, , is characterized by an X X Y system with a neo-Y chromosome for males. Here, a chromosome-level genome was assembled to investigate the origin of neo-Y chromosome to the male . Twenty-three chromosomes corresponding to the male karyotypes were scaffolded to 762-Mb genome with a contig N50 length of 2.18 Mb. A large neo-Y chromosome ( ) in the male genome was also assembled and exhibited high identity to those of the female chromosomes and . Chromosome rearrangements events were detected in the neo-chromosome . Our results suggested that a centric fusion of acrocentric chromosomes and should be responsible for the formation of the X X Y system. The high-quality genome will not only provide a solid foundation for further sex-determining mechanism research in the X X Y system but also facilitate the artificial breeding aiming to improve the yield and disease resistance for .