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Fig. 5. Effect of combined Msx1/Msx2 knockdown on the dorsal/
ventral axis. Embryos were injected into one blastomere at the two-cell
stage with a mixture of 15 ng M1 and 5 ng M2 (A,B) or twice this dose at
the one-cell stage (C). Fluorescein-labeled standard control MO was used
as a tracer in all injections except the one which was used for hybridization
to Xnot, in which case β-galactosidase was used as the tracer. (A)
Expression at stage 14 of the neural plate marker Sox2 was expanded
laterally, while the epidermal boundary, indicated by XK81, retreated to
a corresponding degree. The axial midline is indicated by the dashed
vertical line. (B) Notochord expression at stage 14 of chordin and Xnot1
were not noticeably affected by Msx knockdown. The lateral expression
domains of Xnot1 were largely eliminated, however. Uninjected controls
are shown for comparison (UI). (C)Embryos injected at the one-cell stage
into the ventral marginal zone with 30 ng M1 + 10 ng M2 were cultured
to stage 10.5, fixed and probed for chordin expression. Vegetal views,
with dorsal towards the top of the figure. No significant difference was
observed between injected and uninjected controls (UI). |
