Fig. 3. GSK3ß-GFP is uniformly stable along the animal-vegetal (A-V) axis during cleavage. (A,B) Two frames from a time-lapse 4-D confocal sequence following injection of Lv-GSK3ß-GFP mRNA at the 1-cell stage. The protein is found in all blastomeres during early cleavage and does not appear to be enriched in a specific subcellular compartment. (C) Quantitation of Lv-GSK3ß-GFP turnover following emetine treatment at the 16-cell stage. The protein is equally and highly stable in mesomere, macromere and micromere territories.