How are these oocytes being selected? I am noticing the rejection of multiple oocytes, but I am curious as to why? Anything pertaining to polar bodies?
@mckebb01 They aren't being rejected, just repositioned. The nucleolus is very sticky and will ruin the egg and the needle. So the technician is releasing and repositioning the egg so that the pronuclei are in a better plane of focus and the nucleolus is in a better position away from the path of the needle. Avoiding the polar bodies just helps because they will cause the eggs to shift and that wrecks the position of the nucleus.
@mckebb01 Also, the DNA injected is linearized DNA. Plasmids are toxic so the gene of interest is excised and purified. We use a different technique to eliminate a certain gene (called a knockout) or add a functioning gene (called a knockin). Cloning calls for removing the entire nucleus and replacing it with conditioned nucleus from the animal you are cloning. This requires a great deal of work because cells are programmed to be a certain tissue and they don't like being reset.
How are these oocytes being selected? I am noticing the rejection of multiple oocytes, but I am curious as to why? Anything pertaining to polar bodies?
I THINK - if they are injecting DNA into the nucleus to obtain a certain protein, there are either plasmids injected that are producing any gene products or the new DNA is integrated into the genome.
If you want to clone a whole animal then it's of course necessary to remove the other dna first.... or so
Great video! Reminds me of the good old days. I miss the lab sometimes...
Brianall7s 2 months ago
How are these oocytes being selected? I am noticing the rejection of multiple oocytes, but I am curious as to why? Anything pertaining to polar bodies?
mckebb01 3 months ago
@mckebb01 They aren't being rejected, just repositioned. The nucleolus is very sticky and will ruin the egg and the needle. So the technician is releasing and repositioning the egg so that the pronuclei are in a better plane of focus and the nucleolus is in a better position away from the path of the needle. Avoiding the polar bodies just helps because they will cause the eggs to shift and that wrecks the position of the nucleus.
Brianall7s 2 months ago
@mckebb01 Also, the DNA injected is linearized DNA. Plasmids are toxic so the gene of interest is excised and purified. We use a different technique to eliminate a certain gene (called a knockout) or add a functioning gene (called a knockin). Cloning calls for removing the entire nucleus and replacing it with conditioned nucleus from the animal you are cloning. This requires a great deal of work because cells are programmed to be a certain tissue and they don't like being reset.
Brianall7s 2 months ago
How are these oocytes being selected? I am noticing the rejection of multiple oocytes, but I am curious as to why? Anything pertaining to polar bodies?
mckebb01 3 months ago
Dear lolpvp,
the micropipette on the right is called "holding" the one on the left "injection"
cheers,
Peter
psobies 11 months ago
@psobies Thank you!
lolzpvp 9 months ago
What is the thing called that "sucks" the cell to it?
lolzpvp 11 months ago
Don't you need to remove the DNA in the receiving cell first?
Picaq2 2 years ago
I THINK - if they are injecting DNA into the nucleus to obtain a certain protein, there are either plasmids injected that are producing any gene products or the new DNA is integrated into the genome.
If you want to clone a whole animal then it's of course necessary to remove the other dna first.... or so
0sali 2 years ago
excellent work, makes my concepts clear!
cozpink 2 years ago
This has been flagged as spam show
@cozpink What is the thing called that "sucks" the cell to it?
lolzpvp 11 months ago
what pipette design do you use? I use eppendorf's femtotips and I am not having much success
kbd3z4 3 years ago
Sperm Mediated Gene Transfer is the future of transgenesis.
pelake 4 years ago
Amazing. I think this is the type of videos that made me want to be a scientist.
efrenjo 4 years ago