Fig. 1

Fig. 1 Rel/NFκB negatively regulates dorsal organizer formation.

a Schematic diagrams of NFκB-tkP:dGFP reporter. NFκB BS: consensus sequence of the NFκB-binding element. PolyA: SV40 polyadenylation sequence. b, c NFκB reporter is activated in the dorsal region of early zebrafish embryos. b Whole-mount in situ hybridization (WISH) for dGFP at the indicated stage in NFκB-tkP:dGFP-transgenic embryos. The dGFP-expressing dorsal regions are indicated with red arrowheads. Scale bar = 200 μm. c Double fluorescent in situ hybridization (FISH) for dGFP (green) and chordin (dorsal marker, magenta) in NFκB-tkP:dGFP-transgenic embryos. Animal views with dorsal to the right. Scale bar = 200 μm. d–f Inhibition of NFκB activity by iκbαb leads to expansion of organizer size and dorsal tissue. d WISH for dGFP in NFκB-tkP:dGFP-transgenic embryos, (e) dharma (organizer marker) and chordin in embryos injected with control (mKO2) or iκbαb mRNA at indicated stages. Animal views. Scale bar = 200 μm. Box plots of the angle of marker genes show first and third quartile, median is represented by a line, whiskers indicate the minimum and maximum. Each dot represents one embryo. P-values from unpaired two-tailed t-tests are indicated. f Phenotypes of larvae injected with control (mKO2) or iκbαb mRNA at 27 hpf. The strength of dorsalization was scored using the C1–5 classification scheme. Lateral views with anterior to the left. The loss of ventral tail fin (a typical dorsalization phenotype) is indicated with red arrowheads. Scale bar = 200 μm. g–irel over-expression leads to reduction of organizer size and dorsal tissue. g WISH for dGFP in NFκB-tkP:dGFP-transgenic embryos, (h) dharma and chordin in embryos injected with control (mKO2) or rel mRNA at indicated stages. Scale bar =  200 μm. Box plots of the angle of marker genes show first and third quartile, median is represented by a line, whiskers indicate the minimum and maximum. Each dot represents one embryo. P-values from unpaired two-tailed t-tests are indicated. i Phenotypes of 27 hpf larvae injected with control (mKO2) or rel mRNA. The strength of ventralization was scored. Lateral views with anterior to the left. Scale bar = 200 μm. Source data are provided as a Source Data file.