Topic 12: Embryo Stem Cells

Question 1

describe the characteristics of embryo (blastocyst)

Answer 1

the outside of a blastocyst,
the trophoblast are touripotoent and
the inside, called embryoblast are pluripotent stem cells

Question 2

characteristics of embryonic stem cells

Answer 2

• pluripotent
• can be induced to differniate into different specialized cells by a specific combination and order of culture media
• contain a high level of telomerase

Question 3

explain how embryonic stem cells can be use to create transgenic mice

Answer 3

after being grown in a culture they can be placed back into a mouse

Question 4

what is added to aid pluripotency in embryonic cells?

Answer 4

chromatin regulars: silence genes that induce differentiation
Oct4, Sox2, and Nanog are three transcription factors needed so they dont turn into trophectoderm

Question 5

describe how fibroblast can be reprogrammed in iPS

Answer 5

the set 4 factors are needed (OSKM or Yamanaka)
- Oct4
- Sox2
- Klf4
- Myc

then they can be induced by culture media to be different cells

Question 6

what is the limitations to iPS cells (induced pluripotent stem cells)

Answer 6

• only a few of that revice the OSKM factors will actually become IPS cells
• very slow (more than 10 days)
• requires change in gene expression and chromatin structure

Question 7

how are converted IPS selected?

Answer 7

G418 is added and if they die they are norma but if they survive they are an IPS

Question 8

understand how iPS could be used for treating diseases

Answer 8

diabetes treatment: the IPS or ES cells can produce normal insulin secretin beta islet cells