Fig. 3. Rescue of mys mutant phenotypes by genetic manipulation of CaMKII expression. (A) Phenotypic rescue of structural defects at the third instar NMJ on muscle 4. Black arrowheads indicate type Ib boutons; open arrowheads indicate type 1s boutons. Scale bar: 20 µm. (B) Quantification of synaptic bouton number in mys and CaMKII overexpression mutant animals. In all cases, type I boutons on a minimum of 20 muscle 12 NMJs in hemisegment A2 were quantified. Error bars indicate s.e.m. Asterisks indicate significance relative to wild type. Circles indicate significance relative to each mys mutant without manipulated CaMKII levels. (* or °P<0.05; *** or °°°, P<0.001).