Fig. 4. Injection of cav1-MOs downregulates Cav1 expression. Embryos were injected with control MO (A,C,D,G,H) or cav1-MO1 (I,J) or cav1-MO2 (B,E,F). At 48 hours, control MO injected embryos appear normal (A), whereas embryos injected with cav1-MO2 are curled with disrupted notochords and tails (B). At 28 hours, control MO injected embryos have a normal notochord (C), which is also seen at 48 hours (D). In cav1-MO2 injected embryos the notochord appears `bubbly' and undulating (E) and the undulating notochord is still apparent at 48 hours (F). When embryos are labelled for caveolin with the pan-caveolin antibody at 2 days post fertilisation, control MO injected embryos have normal Cav1 labelling at the cell surface (G) with normal Cav3 labelling in muscle (H), but when embryos are injected with cav1-MO1 at 1.5 ng/embryo, the labelling at the junction of these cells is diminished, although some weak intracellular labelling remains (I). Staining in the muscle is unaffected by cav1-MO1 (J compared with H). (K) Western blot analysis of cav1-MO1 and cav1-MO2 48 hours post injection labelled with the Transduction Laboratories polyclonal caveolin antibody show complete downregulation of Cav1 at 3 ng/embryo as indicated by loss of the band corresponding to caveolin (seen in the control MO lane), 10 µg protein was loaded in each lane and Coomassie Blue staining of the membrane shows equal protein loading. (L) Injection of cav1-MO2 causes the body length to be reduced. The few straight embryos were measured to get fish length (cav1-MO2, n=38; control MO n=37). Error bars are standard deviation. P values were determined using two-tailed t-test for samples with equal variance. Shorter lengths are also observed in curved embryos and with cav1-MO1. (M) Injection of cav1-MO1 at 1.5 ng/embryo causes a reduced number of neuromasts at 72 hours along the posterior lateral line (n=71) compared with control embryos. Neuromasts were identified by DASPEI labelling. (N) Loss of both Cav1 and Cav3 results in a more dramatic phenotype where small rounded cells are still evident at 48 hours. Bars, 250 µm (A,B); 50 µm (C-F,N); 20 µm (G-J).