Fig. 5. Muscle and nerve cord formation in macho-1-deficient and -overexpressing embryos. (A-D) Expression of muscle myosin protein in embryos whose cleavage was arrested at the 110-cell stage. (E-I,E'-G') Expression of HrETR-1 in (E I) cleavage-arrested 110-cell embryos and (E'-G') 118-cell stage embryos without cleavage arrest. (A,E,E') Embryos injected with control MO. Anterior is upwards. (B,F,F') PVC-removed embryos. (C,G,G') Embryos injected with (C,G) 100 pg and (G') 300 pg of macho-1 MO. White arrowheads indicate ectopic expression of HrETR-1. Black arrowheads indicate the posterior blastomeres that show no signal. Anterior is upwards. (D,H) 100 pg of macho-1 mRNA was injected. (I) PVC-transplanted embryo. (J) The vegetal hemisphere of the 110-cell stage embryo. Color of blastomeres is the same as in Fig. 1. Scale bars: 100 µm.