Effects of Bisphenol A on gene expression and DNA damage in adult viviparous fish .

Bisphenol A (BPA) is an emerging pollutant of global concern. Viviparous fish is endemic to the Central Mexican Plateau where BPA was detected; however, few studies examined the influence of this chemical on native viviparous fish. The effects of BPA (sublethal dose) were determined on DNA integrity and expression in gonads, and interactions of BPA with FOXL2 protein.

Gonadal morphogenesis and sex differentiation in the viviparous fish Chapalichthys encaustus (Teleostei, Cyprinodontiformes, Goodeidae).

This study describes the structural and ultrastructural characteristics of gonadal sex differentiation and expression of Vasa, a germline marker, in different developmental stages of embryos and newborn fry of the barred splitfin Chapalichthys encaustus, a viviparous freshwater teleost endemic to Mexico. In stage 2 embryos, the gonadal crest was established; gonadal primordia were located on the coelomic epithelium, formed by scarce germ and somatic cells. At stage 3, the undifferentiated gonad appeared suspended from the mesentery of the developing swimbladder and contained a larger number of germ and somatic cells.

Expression of 3β-HSD1 and P450 Aromatase enzymes during mouse gonad differentiation.

In sheep embryos, steroidogenic activity has been reported as taking place during the period of sexual differentiation. In the case of mouse embryos, the sporadic detection or absence of steroidogenic enzymes suggests that the ovary is inactive. The purpose of this work was to establish if mouse undifferentiated gonads express steroidogenic enzymes in a similar way as in sheep embryos.