Hemostasis Physiology and Clinical correlations by Dr Faiza.pdf
Modulation of pluripotency in the porcine embryo and i ps cells (Dec.27,2012)
1. Modulation of Pluripotency in the
Porcine Embryo and iPS Cells
Rodríguez A, Allegrucci C, Alberio R.
(2012). PLoS ONE 7(11): e49079.
doi:10.1371/journal.pone.0049079
Speakers : Ahmad - Jay – Nan – Fred – Jason
2012-12-27
4. Introduction
*NANOG:
- NANOG is a gene expressed in embryonic stem cells (ESCs) and is thought to be a
key factor in maintaining pluripotency.
- Pluripotency marker gene.
-NANOG is thought to function in concert with other factors such as:
POU5F1 (Oct-4) and SOX2 to establish ESC identity.
* GATA family :
-A family of transcription factors characterized by their ability to bind to the DNA
sequence "GATA" which linked with embryonic cardiac development.
Ex: GATA4 & GATA6
5. Introduction
*FGF (Fibroblast Growth Factors) Signalling Pathway:
- The FGFs are heparin-binding proteins involved in angiogenesis, wound healing, and
embryonic development.
- FGFs are key players in the processes of proliferation and differentiation of wide variety of
cells and tissues.
*MEK Signalling Pathway:
- MEK is a member of kinases involved in cell growth, cell proliferation and cell
survival.
*Wnt Signalling Pathway:
- Wnt is a network of proteins that controls cell-cell communication in the embryo
and adult.
6. Introduction
Aim of this Study :
-Investigation the signalling pathways participating in the formation of the
porcine ICM (Inner Cell Mass).
- Establishing whether their modulation can be used to increase the developmental
potential of pluripotent cells (Pluripotency).
21. MEK and GSK3β Inhibition +LIF
Promotes Naïve iPS Cells
LIF withdrawal or JAK/STAT3 inhibition of cells grown with FCS resulted in a rapid loss
of their compact morphology. These cells showed overt signs of differentiation, which
was confirmed by the expression of SOX17 and NODAL and the reduction in NANOG
expression.
22. 2i/3i + LIF activated genes indicative of
naive pluripotency
overall the cultures in 3i(MEKi, GSK3βi, FGFRi) were more homogeneous and showed
low levels of differentiation
23. Colonies of cells grown in 3i + LIF
STELLA expression correlated with changes in NANOG, OCT-4 and REX1
expression, but were not correlated with FGF5 expression, however high variability
was detected between different lines
25. Naive piPS have Increased Germline
Differentiation Potential
piPS cells expressing STELLA can be efficiently induced to initiate the germ cell
differentiation program in vitro.
32. • MEK, GSK3β inhibition + LIF can impose porcine
embryos into a naive state, but cannot be used to
capture NANOG-only ICM cells.
• iPSCs also can be imposed into naive state.
• STELLAhigh iPSCs had increased capability to
differentiate to VASA-expressing germ cell
precursors.
32