Fig. 7

Induction of gata5 and ntl in embryos injected with RNA encoding constitutively active activin receptor, Alk4* (A-D) or BMP2/7 receptor, Alk2* (E), animal pole views, 50% epiboly. ntl, (red); gata5, (blue); b-gal, (turquoise). (A) 1 mg/ml Alk-4*. There is little alteration to the expression of ntl and gata5. (B) 10 μg/ml Alk4*. The expression of ntl and gata5 is ectopic in the location of cells expressing b-gal. gata5 ectopic expression occurs within the wider area of ntl expression. (C) 100 μg/ml of Alk4*. ntl expression is clearly in regions of the blastula not expressing β-gal whilst gata5 expression remains in the β-gal-expressing cells. This is shown in higher magnification in D. Black arrowhead indicates ntl-expressing cells without nuclear β-gal. gata5 expression is seen as blue cytoplasm in cells with turquoise nuclei (white arrows). (E) 100 μg/ml Alk2*. Normal expression of ntl and gata5.