Fig. 2. dlg-1(ok318) is a strong loss-of-function allele, the phenotypes of which resemble dlg-1(RNAi). (A) Diagram displaying the locations of the dlg-1(ok318) deletions within the dlg-1 open reading frame. Deletion 1 is a 109-bp deletion spanning the third exon-intron boundary. Deletion 2 is a 1368-bp deletion removing most of exon 8 to exon 10. Deletion 1 is predicted to produce a frameshift mutation, truncating the protein after the first 153 amino acids. (B-D) Nomarski images of wild-type and dlg-1 loss-of-function embryos. (B) Wild-type embryo nearing the end of elongation. (E,H) dlg-1(ok318) embryos (E) resemble dlg-1(RNAi) embryos (H), arresting at the twofold stage of elongation and frequently forming large vacuoles (black arrowheads). (C,D,F,G,I,J) Wild-type and dlg-1 mutant embryos stained with anti-DLG-1 or anti-AJM-1 antibodies. In wild-type embryos, both DLG-1 (C) and AJM-1 (D) are well-distributed along the apical junctions of epithelia. DLG-1 protein is undetectable in both dlg-1(ok318) (F) and dlg-1(RNAi) (I) embryos. Similarly, AJM-1 is mislocalized into puncta along the junction in both dlg-1(ok318) (G) and dlg-1(RNAi) (J) embryos. Scale bar: 10 µm.