Sex Maintenance in Mammals.
Genes (Basel)
; 12(7)2021 06 29.
Article
in En
| MEDLINE
| ID: mdl-34209938
ABSTRACT
The crucial event in mammalian sexual differentiation occurs at the embryonic stage of sex determination, when the bipotential gonads differentiate as either testes or ovaries, according to the sex chromosome constitution of the embryo, XY or XX, respectively. Once differentiated, testes produce sexual hormones that induce the subsequent differentiation of the male reproductive tract. On the other hand, the lack of masculinizing hormones in XX embryos permits the formation of the female reproductive tract. It was long assumed that once the gonad is differentiated, this developmental decision is irreversible. However, several findings in the last decade have shown that this is not the case and that a continuous sex maintenance is needed. Deletion of Foxl2 in the adult ovary lead to ovary-to-testis transdifferentiation and deletion of either Dmrt1 or Sox9/Sox8 in the adult testis induces the opposite process. In both cases, mutant gonads were genetically reprogrammed, showing that both the male program in ovaries and the female program in testes must be actively repressed throughout the individual's life. In addition to these transcription factors, other genes and molecular pathways have also been shown to be involved in this antagonism. The aim of this review is to provide an overview of the genetic basis of sex maintenance once the gonad is already differentiated.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sexual Development
/
Mammals
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Genes (Basel)
Year:
2021
Document type:
Article
Affiliation country: