|
|
|
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 3. Dorsoventral patterning of the somite is abnormal in
Gli2–/–Gli3–/–
embryos. Transverse sections through the trunk of wild-type (A), and
Gli2–/–Gli3–/–
(B) embryos at E10.5 were stained to reveal tissue morphology. In
Gli2–/–Gli3–/–
embryos, ectopic epithelium extends ventromedially (open arrowheads), the
sclerotome is reduced and myotome is not distinguishable. dm dermomyotome, scl
sclerotome, my myotome. Expression of Pax3 and Myf5 were
assessed by whole-mount in situ hybridization in wild-type (C,E) and
Gli2–/–Gli3–/–
(D,F) E9.5 embryos. Pax3 in
Gli2–/–Gli3–/–
embryos appeared normal in wholemount. Myf5 expression in
Gli2–/–Gli3–/–
somites was diffuse and expanded laterally. Additionally, dorsomedial-specific
expression (arrowhead in E) was absent (arrowhead in F). Scale bar: 0.5 mm.
(G-R) Expression of Pax3, Sim1, Pax1 and Myf5, were assessed
by whole-mount in situ hybridization and sectioned. Transverse sections though
the trunks of E.9.5 wild-type (G,I,K,O),
Gli2–/–Gli3–/–
(H,J,L,P), Shh–/– (M,Q) and
Shh–/–Gli3–/–
(N,R) embryos were collected. Broken lines outline ectopic epithelium in
H,J,L,P. In
Gli2–/–Gli3–/–
embryos Pax3 is expressed in the ectopic ventromedial epithelium of
Gli2–/–Gli3–/–
somites (arrowhead in H). Sim1 expression is normal in wild-type
(arrowhead in I) and
Gli2–/–Gli3–/–
mutants (arrowhead in J). Pax1 expression is weak in
Gli2–/–Gli3–/–
embryos (L), undetectable in the trunk of
Shh–/– embryos (M), but restored in
Shh–/–Gli3–/–
embryos (N). In wild type, Myf5 is restricted to the layer of myotome
(O), whereas in
Gli2–/–Gli3–/–
somites, Myf5 is expressed throughout the mesenchymal cells within
the epithelial spheres (P). In Shh–/– somites,
dorsomedial expression of Myf5 is reduced (arrowhead in Q), whereas
in
Shh–/–Gli3–/–
somites Myf5 is restored in the dorsomedial lip (R). Scale bar: 50
µm.
|
