ATRA and ESCs

zar

New member
All-trans retinoic acid (RA) is one of the most important morphogens with pleiotropic actions. Its embryonic distribution correlates with neural differentiation in the developing central nervous system. To explore the precise effects of RA on neural differentiation of mouse embryonic stem cells (ESCs), we detected expression of RA nuclear receptors and RA-metabolizing enzymes in mouse ESCs and investigated the roles of RA in adherent monolayer culture. RESULTS: Upon addition of RA, cell differentiation was directed rapidly and exclusively into the neural lineage. Conversely, pharmacological interference with RA signaling suppressed this neural differentiation. Inhibition of fibroblast growth factor (FGF) signaling did not suppress significantly neural differentiation in RA-treated cultures. Pharmacological interference with extracellular signal-regulated kinase (ERK) pathway or activation of Wnt pathway effectively blocked the RA-promoted neural specification. ERK phosphorylation was enhanced in RA-treated cultures at the early stage of differentiation. CONCLUSION: RA can promote neural lineage entry by ESCs in adherent monolayer culture systems. This effect depends on RA signaling and its crosstalk with the ERK and Wnt pathways.
http://www.ncbi.nlm.nih.gov/pubmed/19642999?log$=activity
 

zar

New member
Barbara,
There is nothing else on that page.
Its a pre--publication

-----------------------

OBJECTIVE: To study the role of extracellular matrix (ECM) in neural differentiation of mouse embryonic stem cells (ESCs). METHODS: Mouse ESCs were incubated in the ESC conditioned medium, and the formation of embryonic bodies (EBs) were induced in bacteriological dishes using high-concentration all-trans retinoic acid (RA). The EBs were seeded on different matrixes (gelatin, fibronectin, and laminin/poly-L-ornithine) to test their impact on neural differentiation of the ESCs using immunofluorescence assay. The effect of laminin/poly-L-ornithine on the growth of neurites was evaluated with fluorescence microscopy. RESULTS: High-concentration RA activated and accelerated the differentiation of ESCs toward nestin-positive neural progenitor cells. Fibronectin supplement in the matrix dose-dependently promoted ESC differentiation into neural progenitor cells, while laminin/poly-L-ornithine increased the growth of the neurites and induced the maturation of the differentiated neural cells. CONCLUSION: ECM plays an important role in neural differentiation of mouse ESCs, and application of FN produces the most conspicuous effect during the differentiation of the ESCs into the neural progenitor cells;laminin/poly-L-ornithine is the most effective during their differentiation into neural cells.

http://www.ncbi.nlm.nih.gov/pubmed/19114337?ordinalpos=9&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum&log$=freejr
 
Top