Modulation of pluripotency in the porcine embryo and i ps cells (Dec.27,2012)
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
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 DNAsequence "GATA" which linked with embryonic cardiac development.Ex: GATA4 & GATA6
Introduction*FGF (Fibroblast Growth Factors) Signalling Pathway:- The FGFs are heparin-binding proteins involved in angiogenesis, wound healing, andembryonic development.- FGFs are key players in the processes of proliferation and differentiation of wide variety ofcells and tissues.*MEK Signalling Pathway:- MEK is a member of kinases involved in cell growth, cell proliferation and cellsurvival.*Wnt Signalling Pathway:- Wnt is a network of proteins that controls cell-cell communication in the embryoand adult.
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 developmentalpotential of pluripotent cells (Pluripotency).
MEK and GSK3β Inhibition +LIF Promotes Naïve iPS CellsLIF withdrawal or JAK/STAT3 inhibition of cells grown with FCS resulted in a rapid lossof their compact morphology. These cells showed overt signs of differentiation, whichwas confirmed by the expression of SOX17 and NODAL and the reduction in NANOGexpression.
2i/3i + LIF activated genes indicative of naive pluripotencyoverall the cultures in 3i(MEKi, GSK3βi, FGFRi) were more homogeneous and showed low levels of differentiation
Colonies of cells grown in 3i + LIFSTELLA expression correlated with changes in NANOG, OCT-4 and REX1expression, but were not correlated with FGF5 expression, however high variabilitywas detected between different lines
Differentiation potential of iPS cellsgrown under different conditions
Naive piPS have Increased Germline Differentiation PotentialpiPS cells expressing STELLA can be efficiently induced to initiate the germ celldifferentiation program in vitro.
• 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
Thank you for your attention! Any question? 33