Fig 4. MEX-5/6-mediated translational activation of
era-1. A-D 4-cell embryos expressing YFP-ERA-1[3'
era-1] in control (A),
mex-5/6(RNAi) (B),
par-3(RNAi) (C) and
par-1(RNAi) (D) conditions, stained with antibodies against GFP (green) and GPA-16 (red); DNA is viewed in blue. E Signal intensities at the cell-cell boundaries of ABa/ABp and EMS/P2 relative to GPA-16 (Materials and Methods). Number of embryos quantified: control, n = 10;
mex-5/6(RNAi), n = 10;
par-3(RNAi), n = 9;
par-1(RNAi), n = 10. Statistical analysis was performed using unpaired Student's t-test to compare control with RNAi conditions for both anterior and posterior blastomeres, yielding the following p-values:
mex-5/6(RNAi), anterior: p = 4.4210-7; posterior: p = 1.4610-3;
par-3(RNAi), anterior: p = 9.3210-3 ; posterior: p = 0.04;
par-1(RNAi), anterior: p = 0.741; posterior: p = 1.8110-5. F-G 4-cell embryos expressing YFP-ERA-1[3'
pie-1] in control (F) or upon
mex-5/6(RNAi) (G). Red arrowheads in F indicate cytoplasmic foci resembling endomembranes, suggesting that ERA-1 traffics through endosomal compartments. H Signal intensities at the cell-cell boundaries of ABa/ABp and EMS/P2 relative to GPA-16 (Materials and Methods). Number of embryos quantified: control, n = 10;
mex-5/6(RNAi), n = 8. Statistical analysis was performed using unpaired Student's t-test to compare control with
mex-5/6 (RNAi) for both anterior and posterior blastomeres, yielding the following p-values:
mex-5/6 (RNAi), anterior: p = 0.113; posterior: p = 0.205 Working model of MEX-5/6-mediated control of
era-1 mRNA asymmetric distribution in P0 and translational activation in 2-cell embryos; see also main text.