Mammalian pre and post implantation development Flashcards
When does implantation happen relative to blastocyst development?
After
Where in the oocyte is the maternal complex?
Part of the oocyte membrane
What is the SCMS?
Subcortical maternal complex
Which proteins does the SCMC contain?
MATER, FILIA, TLE6
What is Mater?
maternal antigens that embryos require
What are the proteins in the SCMC important in?
Early development and fertilisation, as well as keeping the embryo alive
What is Dnmt1o?
The oocyte specific DNA methyltransferase
What can happen if SCMC genes are deleted in the oocyte?
Arrests in different stages of the implantation
Role of maternal pioneer factors?
Activating the embryo via interacting with its genome
What is Zelda in fruitflies?
A maternal pioneer factor in fruitflies
How does Zelda work?
It binds to the closed, hyperfolded DNA and moves the nucleosomes apart, allowing TFs to bind to the DNA
Difference in paternal pronuclei in mice?
Male pronuclei is larger
Size of embryo until day 6/7?
The same–> # of cells increases but the size remains the same
WHat happens to the oocyte cytoplasm for the first few rounds of cell division?
It is divided up among the newly forming cells
WHat will the trophectoderm end up being?
Extra embryonic tissue
Where do the primordial germ cells migrate to?
The genital ridge
What happens to the primordial germ cells during their migration to the genital ridge?
They lose their epigenetic marks–> allows them to be “reprogrammed”
How differentiated are sperm and egg cells?
Terminally differentiated
What are cleavage divisions?
A series of cell divisions after fertilization in which the net size of the embryo remains the same
What is compaction?
A process during early embryo development, when blastomeres adhere to each other to form a cluster of cells (the morula).
What is the epiblast?
The part of the embryo containing pluripotent cells that are able to give rise to all the tissues of the fetus.
What is a germinal vesicle oocyte/
An immature oocyte that has a visible nucleus (the germinal vesicle) and is arrested in metaphase I (of meiosis I), prior to ovulation.
What is in the immer cell mass?
pluripotent cells that are able to give rise to all cells of the fetus.
What are the promitive endoderm cells?
Extra-embryonic cells that do not contribute to the fetus; instead, they give rise to extra-embryonic endoderm cells that will form the yolk sac.
