Distribution of the ECM components laminin and nidogen in LanB1S0733and Cg25CS3064mutant embryos. Dorsal views of stage 16–17 embryos stained with antibodies against laminin (A, C, E, G, I) or nidogen and Odd (B, D, F, H, J) as indicated. (A, B) Dorsal vessel of a wild type embryo with contiguous laminin and nidogen layers in the lumen and around the myocardial tube. (C, D) Dorsal vessel of a LanB1S0733 embryo displaying only short stretches of laminin and nidogen deposits and numerous dots or small circles scattered relatively evenly along the tube at about one dot per cardiomyocyte. (E, F) Cg25CS3064 mutant with nearly normal laminin and nidogen distribution. (G, H) Projection of internal sections showing laminin (G) and nidogen (H) staining in basement membranes of other tissues, e.g. around the brain (br), gonad (go), hindgut (hg), midgut (mg) and Malpighian tubules (mt).