Figure 4

Xenopus Mad3 mRNA and protein are present in early embryos. (A) Mad3 mRNA is expressed by animal cells in a symmetric pattern at the stage 3 (4 cells) (I,II,III), at the stage 5 (16 cells) (IV,V,VI) and at the stage 7 (64 cells) (VII,VIII,IX). Figure X: in situ reaction control, animal view (no secondary antibody added to the reaction); XI and XII: no probe added to the reaction, animal and vegetal view, respectively. (B) Immunoblotting using stage 7 (64 cells) whole embryo lysate with an anti-Mad3 antibody. Lane 1: Whole lysate from stage 7 embryos. Anti-Mad3 recognizes a band running at 30 kDa. Lane 2: Immunoblotting control with no primary antibody added to the membrane. Lanes 3 and 4: Whole protein lysate from non injected (lane 3) or Mad3WT-flag injected embryos (lane 4) were used to detect exogenous Mad3.