An NF-κB and Slug Regulatory Loop Active in Early Vertebrate Mesoderm
A: Injection of the Slug MO leads to an increase in TUNEL staining. B: This increase is blocked by the injection of Bcl-xL RNA (600 pg/embryo and co-injected with LacZ RNA). Injected sides of embryos are marked by an “*” and red staining; line marks midline of the embryo, with anterior (“An”) and posterior (“Ps”) indicated. Injection of Bcl-xL RNA (600 pg/embryo) rescues Apod (C- Slug MO injected, D-Slug MO+Bcl-xl RNA injected), Xbra (Ε- Slug MO injected, F-Slug MO+Bcl-xl RNA injected), and Sox9 expression (G- Slug MO injected, H-Slug MO+Bcl-xL RNA injected). I: Injection of Bcl-xL RNA into one cell of a two-cell embryo led to a dramatic increase in the intensity and extent of Slug expression at stage 16; the region of Slug expression on the uninjected (control) side of the embryo is indicated by the dashed circle. J: Injection of Bcl-xL RNA produced an increase in Slug RNA levels in animal caps prepared at stage 8/9 and analyzed by QRT-PCR when uninjected embryos reached stage 11. Ornithine decarboxylase (ODC) was used as normalization control. RNA levels in the control case were set to 100%.