Domains of ventral markers are expanded in cerebum- gastrula. (A,B) Expression of ntl [80% epiboly] in WT (A) and crm mutant embryos (B). Mutants had fewer ntl-expressing cells adjacent to the dorsal axial mesoderm (arrows), and a broader domain of expression ventrally. (C,D) Expression of gata2 [80% epiboly] (arrows) spanned an approximately 120° region on the ventral side in WT (C) but spread to an approximately 315° region of the mutant margin (D). (E,F) Expression of eve1 in WT (E) and crm mutant embryos (F) at early shield stage [50% epiboly]. The expanded domain of eve1 expression is already apparent in the crm- embryo at early gastrulation (arrows). (G,H) Double labeling for expression of gsc and eve1 in WT (G) and mutant (H) embryos at late shield stage [55% epiboly]. Although the pattern of dorsal gsc expression is similar in WT and mutant embryos (brackets), the expansion of eve1 expression into the dorsolateral margin is even more apparent in the mutant at this stage. All embryos are oriented with dorsal to the top; A and B are vegetal pole views, and C-H are animal pole views. Scale bar, 100 μm.
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