XB-IMG-135920
Xenbase Image ID: 135920
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Figure 6. dnXwnt-8 blocks induction of
XMyoDa and Xpo in the ventral and lateral
marginal zone, whereas ectopic Xwnt-8 induces
ectopic expression of these markers in
the dorsal marginal zone. In situ hybridization
(purple staining) of stage 101/4-101/2 embryos
with probes for XMyoDa (A,C,E,G,I) and Xpo
(B,D,F,H,J). (A,B) Control RNA (-3 ng) injections
into the marginal zone of all four blastomeres
of four-cell embryos lead to normal expression
of both the lateral mesodermal marker
XMyoDa (A) and the ventrolateral mesodermal
marker Xpo (B). (C,D) When 0.8-3 pg of
dnXwnt-8 RNA is injected, expression of
XMyoDa is abolished (C) and localized Xpo
RNA staining is greatly reduced (D) (see Table
4A). (E,F) Overexpression of wild-type Xwnt-8
(CSKA Xwnt-8, -100 pg) in one side of the ventrolateral
mesoderm of dnXwnt-8 RNA (-800
pg)-injected embryos rescues the expression of
the mesodermal markers XMyoDa (E, indicated
by arrowheads) and Xpo (F, indicated by arrowheads)
predominantly on the side of injection
(see also Table 4B). (G-J) In a gain-of-function
analysis, CSKA Xwnt-8 DNA (-100 pg) was injected
into the marginal zone of both dorsal
blastomeres at the four-cell stage (L J) to ectopically
express Xwnt-8 in the dorsal prospective
mesoderm. Whereas ventral injected embryos
have the normal dorsal gap of XMyoDa expression
[G, indicated by an open arrowhead; vegetal
view (left) and dorsal view (right) of the
same embryo; see Table 4C], ectopic Xwnt-8
expression results in the ectopic expression of
XMyoDa in most dorsal prospective mesoderm
[L indicated by a solid arrowhead; vegetal view
(left) and dorsal view (right) of the same embryo].
Similarly, whereas uninjected embryos
show only weak Xpo staining on the dorsal side
[H, indicated by an open arrowhead; vegetal
view (left) and dorsal view (right) of the same
embryo; see also Table 4C], ectopic Xwnt-8 expression
also causes strong expression of Xpo in
the dorsal prospective mesoderm [J, indicated
by a solid arrowhead, vegetal view (left) and
dorsal view (right) of the same embryo]. Image published in: Hoppler S et al. (1996) Copyright © 1996. Image reproduced on with permission of the Publisher, Cold Spring Harbor Laboratory Press. This is an Open Access article. Larger Image Printer Friendly View |