Xenbase Image ID: 23925

Fig. 2. Hairy2 transiently activates Delta1. (A) Dorsal views of neurula embryos showing Delta1 upregulation upon Hairy2-GR, Hairy2DBM-GR or Hes1-GR injection (500 pg mRNA) (a, 72%, n = 22;b, 83%, n = 36; c, 68%, n = 16, respectively). Q-PCR analysis of Delta1 expression at different time points until tadpole stage in animal caps derived from embryos injected with noggin + Wnt8 overexpressing or not Hairy2-GR mRNA (250 pg/blastomere), with DEX added at the equivalent of stage 12. Note the rapid and transient activation of Delta1 (d). Antero-dorsal view of a late neurula Hairy2 depleted embryo with reduced Delta1 expression in the NC migrating streams (75%, n = 20) (e). Hairy2 MOs (10 ng/blastomere) decreases Delta1 expression in animal caps induced to NC at the equivalent of stage 14 (f). (B) Double in situ hybridization showing that Delta1 (purple) and Hairy2 (light blue) expressions overlap in the anterior portion of the lateral neural plate border (arrows) (a). Higher magnification of the lateral neural plate border (a′) and cross section through its anterior portion (a′) are shown. (C) Whole-mount in situ hybridization of Delta1 expression in neurula embryos injected with Id3-GR (1 ng), Hairy2-GR (500 pg) and Id3-GR mRNA (1 ng) or Id3 MO (15 ng). Note that Id3 reduces Delta1 (a, 50% inhibited, n = 18) and counteracts Hairy2 activation of Delta1 (b, 73% unaffected, n = 30) while injection of Id3 MO (15 ng) upregulates its expression (c, 60% upregulated, n = 25). Q-PCR analysis of Delta1 expression in NC induced explants derived from embryos injected with Hairy2 MOs (10 ng/blastomere) or Id3 MO (15 ng/blastomere) as indicated (−, uninjected NC induced caps) (d). Note that Id3 depletion upregulates Delta1 and that Hairy2 knockdown and the double knockdown of Id3 and Hairy2 result in Delta1 inhibition. In all in situ panels, neurula embryos are viewed from the dorsal side. LacZ was used to identify the injected side (right side). Image published in: Nichane M et al. (2008) Copyright © 2008. Image reproduced with permission of the Publisher, Elsevier B. V. Gene Synonyms Species Stage(s) Tissue dll1 delta-1, Delta-1, delta1, x-delta, X-delta-1, Xdelta-1, Xdelta1, XDelta1 Xenopus Throughout NF stage 17 neural crest anterior neural ridge pre-chordal neural plate border chordal neural plate border anterior neural fold hes4 H2, hairy2, hairy2a, hairy2b, hes4-a, hes4-b, hes4a, hes4b, Xhairy2, XHairy2a, Xhairy2b Xenopus Throughout NF stage 17 neural crest anterior neural ridge chordal neural plate dll1 delta-1, Delta-1, delta1, x-delta, X-delta-1, Xdelta-1, Xdelta1, XDelta1 Xenopus Throughout NF stage 20 neural crest migratory neural crest cell anterior neural fold anterior neural tube neural tube Image source: Published Larger Image Printer Friendly View

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