(A) A representative image of ToLFP labelling patterns from N2, ced-3 and ced-1 embryos. The same embryo of N2 is shown in a phase image (a) and fluorescence image (b), a ced-3 embryo in a fluorescence image (c) and a ced-1 embryo in a fluorescence image (d). The imaginary line in (a) and (b) indicates anterior (A) and posterior (P) half of embryo. Scale bar: 20 μm. (B) An in vitro assay of DNase II activity. Embryo extracts from N2, ced-3 and ced-1 were analysed the DNase II activity under the condition of pH 7.5 (lane 1–3) or pH 4.5 (lane 4–12). The samples of each strain were collected and analysed at three time points: 0, 15 and 30 min. The lysates from various genetic background worms are indicated above the gel. M lane shows DNA ladder markers. (C) The Western blot analysis of actin is used as loading amount of lysates. (D) Quantitative analysis of ToLFP number of whole embryos. A series section of images (a–l) from a single N2 embryo shows the total ToLFP signals (labelled with numbers). (E) A series section of images (a–l) from a single ced-1 embryo shows the total ToLFP signals (labelled with numbers). Scale bar: 20 μm.