Fig. 2. Spatial expression of Xfz7. In situ hybridization on whole
embryos (A-D) and on sections (E-J). (A) Dorsovegetal view of a
stage 10 gastrula. Xfz7 is strongly expressed in the blastoporal lip and
in the presumptive neuroectoderm, with a gap of lower expression
levels between these two regions. (B) Dorsovegetal view of a stage
11 gastrula. The presumptive neuroectoderm is strongly stained.
(C) Lithium-dorsalized early gastrula shows expression of Xfz7 in the
entire marginal zone. (D) U.v.-ventralized early gastrula shows
absence of Xfz7 expression. (E) Sagittal section of a stage 10.5
gastrula. (F) Higher magnification of E. Xfz7 transcripts are strongly
expressed in the presumptive neuroectoderm (ne) and in deep cells of
the dorsal mesoderm, located between the Brachetâ s cleft (b) and the
superficial layers (arrow). (G) Sagittal section of a stage 11 gastrula.
(H) Higher magnification of G. Strong expression of Xfz7 is present
in the presumptive neuroectoderm and in deep layers of dorsal
mesoderm (arrowheads). Lower levels of expression are present in
the superficial layers (arrows). (I,J) Transverse section from a stage
18 neurula. Anteriorly (I), Xfz7 is expressed in the neural plate and in
the lateral plate mesoderm (lp), but not in the somites (s). Posteriorly
(J), it is expressed in the unsegmented somitic mesoderm.