Figure 6

An over-expression of Cys-less UNC-7 does not cause dominant negative effect. (A) An over-expression of Cys-less UNC-7 mutant proteins did not have effect on active zone morphology. Wild type animals carrying the GFP::UNC-10 active zone marker were injected with a plasmid expressing Cys-less UNC-7 proteins. Morphology (left panels) and total number (right panel) of dorsal GFP::UNC-10 puncta were comparable in non-transgenic (wt) or transgenic (wt + Cys-less UNC-7) animals. Scale bar: 5 μm. (B) An over-expression of the Cys-less UNC-7 mutant proteins in wild type animals did not change the mPSC frequency or amplitude. Representative traces of mPSC recording from wild type (wt) animals or animals expressing Cys-less UNC-7 (wt + Cys-less UNC-7) were shown (left panel), and mPSC amplitude and frequency quantified (right panel). (C) An over-expression of wild type, Cys-less and C191A UNC-7 proteins in unc-7 mutant background. Wild type UNC-7 protein, but not the two mutant UNC-7 proteins, rescued active zone morphology defect. Total number of dorsal GFP::UNC-10 puncta were quantified and normalized to that of unc-7. Scale bar: 5 μm.