Stem Cells III Flashcards
(27 cards)
MAPK signaling is mediated by which protein?
Erk
What is the role of MAPK signaling?
Predisposes mouse ESCs to differentiation commitment
When can ESCs be established without LIF and serum?
When Erk is suppressed by a combination of Erk inhibitors
MAPK signaling is stimulated by which growth factor?
FGF4
LIF and BMP4 (enable/counteract) the action of MAPK signaling that induces differentiation commitment
Counteract
What are the intrinsic factors that regulate ESC self-renewal?
Oct4, Nanog, Sox2
Oct4-negative embryos differentiate to what in vitro?
Trophectoderm
Oct4 (downregulation/upregulation) is the trigger for the formation of the primitive endoderm
Upregulation
Nanog over-expression leads to the formation of what cells?
LIF independent ESCs
Nanog KO leads to the formation of what type of cells?
Primitive endoderm
Altering the gene dosage of which intrinsic factors modifies the pluripotent phenotype of ESCs?
Oct4 and Nanog
What are some active genes regulated by Oct4, Nanog and Sox2?
FGF2, STAT3
What are some silent genes regulated by Oct4, Nanog and Sox2?
HOXB1, PAX6
What are some pros of ESC application in the clinical setting?
Indefinite source of tissue engineering, any cell type can be produced, genetic manipulation, tissue regeneration
What are the cons of using ESCs in the clinical setting?
Tumorigenicity, low efficiency of differentiated target cells, immunocompatibility, ethics
What is the biological significance of animal cloning?
Differentiated cells retain a complete set of genetic information
Oocyte cytoplasm can reprogram somatic nuclei
What experiment was done to see if ESCs can be generated from committed or terminally differentiated cells?
24 different genes selected from genes expressed in both oocytes and ESCs
Those genes were introduced into fibroblasts
One or combination of genes omitted to see what happens
What was the results of omitting gene 7?
Production of ESCs
Match the role of the Yamanaka factors to Oct4 and Sox2, c-Myc or KIf4
a. Serves as a co-factor for Oct4 and Sox2 and inhibits cell death
b. Restore and maintain pluripotency
c. Disrupts chromatin and allow Oct4 and Sox2 access to the genome
a. KIf4
b. Oct4 and Sox2
c. c-Myc
How are ESCs and iPSCs similar?
Long term self-renewal activity
Pluripotent fibroblasts contribute to the __________ of a developing fetus
Tissues
Why are ESCs and iPSCs not identical?
No live birth of chimeric offspring, global gene expression and DNA methylation patterns
Oct4, Nanog and Sox2 (negatively/positively) control the expression of each other
Positively
What is the consequence of the forced activation of the network using Oct4, Sox2, c-Myc and KIf4?
Reprogramming of somatic cells to iSCs
