Conclusion
Relative ratio of Wnt3a to BMP4 doses is critical to their synergistic effect on differentiating mESC proliferation, which may work through PI-3K, p38, ERK1/2 and JNK pathways.
Methods
Mouse embryonic stem cells were cultured with differing combinations of Wnt3a, BMP4 and inhibitors of Wnt, BMP, PI-3K (phosphoinositide 3-kinase), p38, ERK1/2 (extracellular signal-regulated kinase 1/2) and JNK (c-Jun N-terminal kinase) pathways.
Results
We found that Wnt3a synergized with BMP4 to promote mESC proliferation. Furthermore, the relative ratio of Wnt3a to BMP4 doses was critical to their synergistic effects, which could be abolished by using Dkk-1, noggin or the inhibitors of PI-3K, p38, ERK1/2 and JNK pathways. We also demonstrated that combination of Wnt3a and BMP4 could suppress ectodermal differentiation of mESCs. Moreover, inhibitors of PI-3K, p38, ERK1/2 and JNK pathways could negate this effect.