Geminin Orchestrates Somite Formation by Regulating Fgf8 and Notch Signaling

Figure 3

Notch activity in geminin morphants and the role of Notch in somitogenesis. (a, b) To compare with the expression of DeltaD in control (a, 88.5%, n=35), deltaD was downregulated in geminin morphants (b, 82.2%, n=45). The stripes of deltaD in new forming somite displayed wild “salt and pepper” way (a, b, arrow showed). (c, d) The downstream gene of Notch signal her4 was also downregulated in the embryos injected with GemMO (d, 85.7%, 49), while the expression of her4 was normal in control embryos (c, 82.8%, n=35). (e, f) The cyclic gene her1 was normal in the embryos treated with DMSO (e, 100%, n=22); the oscillation of her1 was blocked in the embryos treated with DAPT (f, 100%, n=18). Overexpression of NICD in the right side of the embryos (g, right side) resulted in disrupted somite segmentation (h, right side). (i-k) Comparing with that in control (i, 86.3%, n=22) and geminin morphants (j, 71.4%, n=28), the expression pattern and quantity were partially restored by coinjecting low dose of NICD mRNA (k, 53.2%, n=32). Bar, 100μM.

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