Fig. S1

Controls for mgaMOs used in this study, related to Figure 2. (A) Western blot from extracts of 75% epiboly mgaMO>1-cell morphants, probed with anti- MgaI or β-tubulin antibodies. TLMO1 Upper band: 6% ± 0.7 S.D. of control levels, Lower band: 30% ± 3.5 S.D. of control levels (not shown); TLMO2 Upper band: 28% ± 4.2 S.D. of control levels, Lower band: 39% ± 2.1 S.D. of control levels; TLMO3 Upper band: is 5% ± 0.7 S.D. of control levels, short isoform is 29% ± 1.4 S.D. of control levels (not shown). (A′) Western blot from extracts of 75% epiboly wildtype embryos, probed with anti-MgaN or anti-MgaC -­6-­ antibodies. The 250Kd and 290Kd bands are apparent in both lanes. (B, C, D, E, H, I) Image of live embryos at the prim-5 stage (24 hpf), injected at the 1-cell stage with 4ng each of mgamisMOTL3 and p53MO or mgaMOTL3 and p53MO (C, D), or injected into the YSL with 150pg IgG or anti-Max antibody (D, E, H, I). (F, G) eve1 expression in mgamisMO>YSL or mgaMO>YSL morphants. (J) Frequency of embryos with defects shown in panel (C) (red) in mgaTL1/3MO>1-cell morphants or mgaTL3MO>1-cell morphants injected with 50pg mRNA encoding either β-galactosidase or mouse mga mRNA. (K) Frequency of embryos lacking ventral tailfins (red) in mgaTL1MO>YSL morphants or mgaTL3MO>YSL morphants injected either with 50pg mRNA encoding β-galactosidase or mouse mga mRNA, or with 50pg DNA encoding zebrafish mga expressed under control of the CMV promoter or empty vector. Note that the pCS2+ zebrafish mga construct lacks sequences targeted by mgaTLMO3 but contains sequences targeted by mgaTLMO1. The mouse mga mRNA is not recognized by either MO. *pd0.05, **pd0.005, ***pd0.0005.