Fig. 3. Th and Dbh expression is restored in the sympathetic ganglia of Tg^hDBH-G3-rescued Gata3^-/- embryos. (A) mRNA levels in the trunk region of individual E10.5 embryos (normalized to GAPDH mRNA) were assayed by real-time Q-PCR. Data were collected from individual E10.5 embryos of Gata3^-/- (5), Gata3^-/-:Tg^hDBH-G3 (4) or wild-type (3) genotypes. Data are presented as mean±s.e.m. The statistical significance of differences between Gata3^+/+ and Gata3^-/- are indicated (^**P<0.01; Student's t-test). (B) E10.5 wild-type embryos display strong Th expression in the sympathetic ganglia (SG; arrowhead) as well as weaker Th immunoreactivity in the ventrolateral neural tube (NT; arrow). (C) In E10.5 Gata3 mutant embryos, Th expression is significantly reduced in both the SG and NT. (D) The hDBH promoter directs transgenic eGFP expression in the SG and the NT in E10.5 embryos. (E) Th immunoreactivity was significantly restored both in the SG and NT of E10.5 transgenic rescued Gata3-null mutants. (F) E12.5 wild-type embryos display strong Th expression solely in the SG, and not in the NT. (G) Th expression is absent in E12.5 Gata3 mutant SG. (H) Transgenic eGFP expression was strong in the SG, but much weaker at E12.5 than at E10.5 in the NT. (I) Th expression was restored solely in the SG of E12.5 Tg-rescued Gata3 mutant embryos. White lines indicate the outer margin of the spinal cord and dorsal root ganglia. DA, dorsal aorta; V, vertebrae.