Two phases of gonadal sex differentiation in zebrafish with ZZ/ZW sex determination system

Gen Comp Endocrinol. 2024 Nov 1:358:114613. doi: 10.1016/j.ygcen.2024.114613. Epub 2024 Sep 19.

Abstract

Zebrafish sex chromosomes have been identified in the wild Nadia (NA) strain, and its sex determination belongs to the female-heterogametic ZZ/ZW system. Here, we investigate the correlation between ZZ/ZW sex chromosomes in the NA strain with sex-related factors, and sort out the complicated process of sex determination in zebrafish. Two phases exist during zebrafish sex differentiation. In the first phase, ZW gonads differentiate into juvenile ovary while ZZ gonads remain indifferent. In the second phase, ZW gonads either continue ovary development or undergo female-to-male transition, while ZZ gonads undergo direct male development. The W chromosome may contribute to the first phase while the abundance of germ cells and other factors may be involved in the second phase of sex differentiation in zebrafish.

Keywords: Oocyte; Ovary; Sex chromosome; Testis.

MeSH terms

  • Animals
  • Female
  • Gonads* / growth & development
  • Gonads* / metabolism
  • Male
  • Ovary / growth & development
  • Ovary / metabolism
  • Sex Chromosomes* / genetics
  • Sex Determination Processes* / genetics
  • Sex Determination Processes* / physiology
  • Sex Differentiation* / genetics
  • Sex Differentiation* / physiology
  • Zebrafish* / genetics