Fig. 3

NMJ postsynaptic fragmentation and impaired apposition of the pre- and postsynapse in Megf10 KO mice. (A) Representative images of the NMJ presynapse labeled against synaptophysin (cyan) and and postsynaptic nicotinic acetylcholine receptors (nAChRs) labeled with fBTX (red) from male juvenile WT and Megf10 KO diaphragm muscles. (B) Male and (C) female postsynapses were analyzed for the proportion NMJs with postsynaptic fragmentation (> 4 distinct nAChR islands). Young adult male diaphragms were then analyzed for postsynaptic (D) receptor area (area of nAChRs), (E) junctional area (area of a perimeter around the nAChRs), and (F) dispersion index (receptor area / junctional area). In young adult male diaphragms, the apposition of the pre- and postsynaptic stains for the NMJ was assessed to determine the (G) innervation status (proportion of the postsynaptic nAChRs innervated by the motor axon terminal) and (H) postsynaptic coverage (proportion of the motor axon terminal apposed by postsynaptic nAChRs). Two-way ANOVA with Tukey’s multiple comparison test (B) or unpaired two-sided Student’s t-test (C-H) for statistical analysis. Values represented as mean + SD. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001 versus WT. ^††††p < 0.0001 versus juvenile. JU (juvenile, 1mo), YA (young adult, 3 mo), MA (middle-aged, 12-14 mo)