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Fig. 3. Knockdown of Xhex function perturbs the organiser and causes loss of anterior structures. In vitro translation assay (A) shows that Xhex antisense
morpholino oligonucleotide (MO) specifically prevents translation of Xhex but not the related mouse Hex. Comparison of Xhex and mouse Hex sequences over
the region MO is designed against, with mismatches between mouse Hexand MO highlighted by asterisks (B). Xhex MO injection into both blastomeres at the
two-cell stage severely affects anterior development and compromises overall A-P patterning (C, upper and lower embryo are examples of severely affected
embryos). Control siblings (D) show wild-type XBF1/En2/Krox20 expression while Xhex MO-injected embryos (C) exhibit reduced or no expression of these
regional markers. Anterior is to the left. Stage 10 Xhex MO-injected embryos display ectopic goosecoid (gsc) expression throughout the animal hemisphere (E,
31%, n 32) while wild-type (WT) siblings express gsc in its normal dorsal domain (F). Xhex MO-injected embryos show reduced chordinexpression (G,
48%, n 21) compared to the normal expression in wild-type controls (H). Embryos are bisected (E,F) and dorsal is to the right. Staining with antibodies
MZ15 (notochord; grey) and 12/101 (muscle; brown) reveals that Xhex MO-injected embryos (I) do not develop correctly segmented somitic muscle compared
to controls (J). Anterior is to the left in both cases. |
