Fig. 5
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Fig. 5 Gene expression characteristic of neural crest is absent, but of the neural plate border and pre-placodal region is present in tfap2a/c deficient embryos. (A, B) Lateral views of 22 hpf embryos processed to reveal sox10 expression, which is present in migratory neural crest streams (arrowheads) and the otic vesicle (ot) in panel A, a control embryo; in panel B, a tfap2a-/cMO embryo, it is only present in the ot (11 of 11 tfap2a-/cMO embryos). (C, D) Dorsal views of 24 hpf embryos processed to reveal dlx2 expression, which is present in cranial migratory neural crest streams (arrowheads) and brain in panel C, a control embryo, but only in the latter in panel D, a tfap2a/c deficient embryo (10 of 10 tfap2a-/cMO embryos). (E–N) Dorsal views of flat-mounted, 11 hpf embryos processed to reveal the indicated markers. foxd3 and snai1b expression that are characteristic of premigratory neural crest (pnc) cells are absent in embryos injected with tfap2a e2i2 MO and tfap2c e3i3 MO (hereafter, tfap2aMO/cMO embryo) (foxd3, 27 of 27 tfap2aMO/c MO embryos; snai1b, 29 of 29 tfap2aMO/cMO embryos. Also not shown, at the same stage, sox10, 29 of 29 tfap2aMO/cMO embryos). Expression of pax3, msxb and dlx3b expression appear normal in tfap2aMO/cMO embryos (100%, n is greater or equal to 30 tfap2aMO/cMO embryos for each gene, also not shown, zic2b). Scale bars: 100 μm.
Reprinted from Developmental Biology, 304(1), Li, W., and Cornell, R.A., Redundant activities of Tfap2a and Tfap2c are required for neural crest induction and development of other non-neural ectoderm derivatives in zebrafish embryos, 338-354, Copyright (2007) with permission from Elsevier. Full text @ Dev. Biol.