Figure 4.—

CEH-39 accumulates in nuclei of young embryos, consistent with its role as an XSE, and also in germline nuclei. (A–D) Partial projections of false-colored confocal images of wild-type and ceh-39 mutant embryos stained with DAPI (red) and antibodies (CA1184) against CEH-39 (green). (A and B) CEH-39 localizes in a diffuse pattern within interphase nuclei of young (50-cell) and older (150- to 200-cell) XX embryos; CEH-39 also associates with mitotic chromosomes (arrow and inset in A). (C) CEH-39 is greatly reduced in embryos with >200 cells. (D) No CEH-39 antibody staining was detectable in ceh-39 deletion mutant embryos, which lack the antibody epitope, demonstrating specificity of the CEH-39 antibody. Bars, 10 μm. (E and F) Partial projections of false-colored confocal images of wild-type and ceh-39 mutant gonads stained with DAPI (red) and CEH-39 antibodies (green) (CA1183). Two focal planes (separated by a dashed white line in E) were used to show pachytene and diplotene diakinesis. In late pachytene and early diplotene, CEH-39 staining appears diffuse nuclear and excluded from the nucleolus. In late diplotene and diakinesis, staining colocalizes with condensed chromosomes. Enlargement of the nucleus in diakinesis is shown in insets in E. Staining is absent in gonads of ceh-39 deletion mutants.