| |
FIG. 6. DRAGON potentiates BMP
signaling in Xenopus embryos. A, microinjection
of mouse DRAGON mRNA in
Xenopus laevis embryos at gastrula
stages synergizes with Smad1 (mRNA injection)
to induce mesodermal (xBra and
mix1) and endodermal (mixer) markers,
as assessed by reverse transcription (RT)-
PCR. No induction of EK or Sox2 occurs.
B, in animal cap explants DRAGON
mRNA injection induces expression of the
anterior neural markers nrp1 and Otx2,
as well the as cement gland marker (Xag)
and nkx2.5, a heart marker. Orthidine
decarboxylase (ODC) is the loading control.
C, Xenopus embryos were injected in
the animal pole of one of two cells at the
two-cell stage with DRAGON mRNA and
analyzed at late neurula (stage 23), for
changes in neural crest patterning, and
early tadpole stages (stage 28) for ectopic
induction of neural tissue. DRAGON
overexpression inhibits twist RNA, a neural
crest marker (top panels), and induces
ectopic patches of N-tubulin, a neural
marker (lower panels). |
