dmrt3, nom1, abce1, and pkmyt1 play key roles in gonadal sex determination in Acrossocheilus fasciatus

Acrossocheilus fasciatus is an economically valuable freshwater fish species that inhabits streams. Female A. fasciatus grow faster and taste better than males, while male show dramatic color and mainly be considered ornamental fish. Numerous farms are trying to breeding an all-female or all-male pedigree. However, little research has been reported on sex determination and gonadal development in A. fasciatus . Genetic and genomic information on its reproduction is also lacking, greatly limiting its breeding and genetic manipulation. To define its genetic background and determine whether there are unique mechanisms in A. fasciatus gonadal development, we utilized transcriptome information from A. fasciatus to recognize genes possibly included in sex determination and gonadal development. Ten sex determining genes significantly up- or downregulated were filtered through the DEGs data: ATP-binding cassette sub-family E member 1 ( abce1 ); nucleolar MIF4G domain-containing protein 1-like ( nom1 ); protein kinase membrane associated tyrosine/threonine 1 ( pkmyt1 ); prostacyclin receptor-like ( ptgir ); homo box protein six ( six1 ); small nuclear ribonucleoprotein A-like ( snpra ); Wnt family member 4 ( wnt4 ); double sex- and mab-3-related transcription factor 3a ( dmrt3 ); E2-alpha-like ( e2a ); and winged helix/forkhead transcription factor L2 ( foxl2 ). The expression patterns of these genes have been checked by way of qRT-PCR during different stages of gonad development. dmrt3 was significantly upregulated in males all through the gonad development stages and might play key positions in testis development. Foxl2 expression was not significantly higher in females, whereas nom1 , abce1 , and pkmyt1 were continuously highly expressed. Our results indicate that some of the crucial sex determination genes show unique expression patterns in A. fasciatus . These findings may enable the manipulation of sex determination genes and the cultivation of new varieties, as well as the exploration of evolutionary processes of fish sex determination mechanisms.