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Fig. 4. Post-otic neural crest cell alterations in RA-rescued
Raldh2/ embryos. (A-D) Whole-mount in situ
analysis of EphA4 (A,B) and EphA2 (C,D) transcripts in E9.5
wild-type (A,C) and Raldh2/ (B,D) embryos.
In (D), EphA2-labeled cells are confined dorsally to the foregut
pocket (arrowhead). E-I, Distribution of Crabp1 transcripts in E9.5
wild-type (E,H) and Raldh2/ (F,G,I) embryos.
(E-G) Profile and (H,I) dorsal views. Brackets in F,G delineate the mutant
post-otic NCC populations (which normally would colonize the 3rd, 4th and 6th
branchial arches). An asterisk in G indicates cells that are abnormally
confined along the dorsal foregut wall, and may correspond in part to pre-otic
(r4-derived) NCC. Mutant embryos also exhibit abnormal patterns of
connectivity between the post-otic hindbrain and NCCs (arrowheads and bracket
in H and I, respectively). b1-b6, branchial arches; fg, foregut; fl, forelimb
bud; ot, otocyst; p1-p3, pharyngeal pouches; r3-r6, rhombomeres.