| |
Fig. 3. PFKFB4 low-level depletion delays NC
early specification, causes retention of NB
character, and impairs NC late specification and
migration. (A) At st.14, snail2 expression was
severely reduced, or abolished, on the injected side.
(B) At st.18, sibling embryos had recovered snail2
expression. (C,D) Whereas sox10 expression was
mainly unaffected, twist1 was severely impaired.
(E-H) In contrast, expression of the immature NC
marker hes4 was expanded, as were some NB
markers, either strongly ( pax3) or moderately (zic1).
Other NB markers were unperturbed (msx1).
(I-K) Neural plate (sox2), non-neural ectoderm (ep.
ker.) and paraxial mesoderm (myod) seemed to be
unaffected. A-K: dorsal views. (L) Percentage of
embryos with each phenotype, i.e. diminished,
increased or normal expression. Snail2 score at
st.14 is indicated as the first bar, then several gene
scores at st.18 are indicated in the following ten
bars. (M-R) St.24 tailbud embryos exhibited a
severe NC migration defect (M-Q). Sox2 expression
appeared grossly unaffected, despite marginal
reduction of optic vesicle size (R). The injected side
(inj) is compared with the control side (co) in side
views (M,N,P,Q, anterior to the right) or frontal views
(O,R; red arrow on injected side). (S) Co-injection of
pfkfb4 mRNA with PFKFBMO rescued both
sox10/twist1 alterations of expression and NC
migration defects in a significant proportion of the
embryos, compared with PFKFB4MO injections
alone. sox10 and twist1 expression were restored or
increased a majority of the embryos. Scale bar:
500 μm. Phenotype scores are shown in Table S8. |
