sexual differentiation Flashcards
What is the main protein that initiates male sexual differentiation?
SRY protein
TDF and SOX9
male differentiation into seminaferious tubules
testosterone and AMH
testes
Male sex determination
begins at
~6-8w
- Steroid hormone secreted by the Leydig cells
- Responsible for maintenance of Wolffian duct structures
- Increases expression of 5𝛼-reductase that converts T to DHT
testosterone
- Peptide hormone secreted by the Sertoli cells
- Responsible for regression of Mullerian duct structures
AMH
- Peptide expressed in the somatic cells of the testes
- Responsible for expression of proteins that will initiate differentiation of indeterminate gonads into testes
TDF
- Gene located on chromosome 17
- Transcription is initiated by TDF
- Acts as a transcription factor
- Initially works with TDF then takes over to complete differentiation of the testes when TDF expression ceases
SOX9
WNT4, Rspo1 and Beta-catenin
female differentiation
external genitalia in the presence of DHT
male differentiation
leydig cells respond to LH or FSH?
LH
Excess androgen action in XX female
Congenital adrenal hyperplasia (CAH)
Deficient androgen action in XY male (2)
- Partial androgen insensitivity syndrome (Reifenstein’s syndrome)
- 5α-reductase deficiency
Aromatase is expressed in ______ tissue
adipose
Chromosomal abnormality causes a child to be born with two different gonads: a testis and a dysgenetic (malformed) “streak” gonad.
Mixed gonadal dysgenesis
