gop-1 is required for cell corpse removal. (A) DIC and fluorescent images of wild-type and gop-1(tm5384) embryos expressing Annexin V::GFP. Cell corpses were identified by their raised button–like morphology and surface-exposed phosphatidylserine indicated by Annexin V::GFP labeling (arrowheads). The percentage of cell corpses labeled by Annexin V::GFP was quantified and is shown as mean ± SD at right. Unpaired t test was performed to compare data derived from wild type with that of gop-1(tm5384). No significant difference was observed. Bar, 2.5 µm. (B, C, G, and H) Time-course analysis of cell corpse appearance during embryonic (B and G) and germline (C and H) development was performed in the indicated strains. The y axis indicates the number of cell corpses. At least 15 animals were scored in each strain at each stage, and data are shown as mean ± SD. Data derived from different genetic backgrounds at multiple developmental stages were compared by two-way ANOVA followed by Bonferroni posttest. *, P < 0.05; **, P < 0.001; N.S., not significant. (D) Embryonic cell deaths occurring 200–380 min after the first cleavage were followed in wild type (WT; n = 3) and gop-1(tm5384) mutants (n = 3). The mean number of total cell deaths (± SD) is shown in parentheses. The y axis indicates the number of cell deaths at each time point. (E and F) Cell corpse duration in soma (E) and germ line (F) was analyzed by 4D microscopy in WT and gop-1(tm5384) mutants. 33 somatic cell corpses or 25 germ cell corpses were examined in each strain. The mean duration time of cell corpses (± SD) is shown in parentheses.