Gametogenesis (spermatogenesis) III (2nd lecture) Flashcards
(30 cards)
What is spermatogenesis?
Male gametogenesis
What is the default sex?
Female
How does development occur is there is no Sry?
Female
What is the testis determining factor?
Sry
What is Sry?
A TF that activates Sox9
What is responsible for upregulating anti-Mullerian hormone (AMH)?
Sox9 and steroidogenic factor 1
What does Sry specifically induce?
Sex cords that form seminiferous tubules
What are sex cords?
embryonic structures that develop within the gonads and play a crucial role in the development of reproductive tissues
What do sertoli cells secrete?
Anti-mullerian hormone
Why do Sertoli cells secrete AMH?
To prevent female development
What do leydig cells do?
Secrete testosterone
Why do leydig cells secrete testosterone?
To promote development of the male reproductive system
What does testosterone promote development of?
Mesonephric duct
What structure does anti mullerian hormone prevent the formation of?
Paramesonephric duct
What are gonocytes?
PGCs in the male at the time of birth
What do gonocytes differentiate into?
Type A spermatogonia
When does male spermatogenesis initiate?
Puberty
How are the sperm cells initially linked?
Cytoplasmic bridges
Role of sertoli cells?
Secrete molecules used in spermatogenesis
What concentrations of GDNF and SCF favour differentiation of spermatogonia?
Low GDNF
High SCF
What is SCF?
Stem cell factor (steel) produced by sertoli cells
What does SCF bind?
c-Kit, an RTK
When does the last mitotic division occur?
Between type B spermatogonia and primary spermatocytes
What stages do differentiating spermatogonia through?
A1–>4, Intermediate, type B, PreLep
