Figure 3.

Focal misalignment of AChR and AChE at synapses in biglycan null mice. A, Hindlimb muscles from 5-week-old wild-type (top) and biglycan null (bottom) littermates were dissected, fixed, and labeled with rh-α-bungarotoxin (red) and OG-fasciculin2 (green) to visualize AChR and AChE, respectively. The AChR and AChE distributions are superimposable in the WT. However, AChE domains lacking subadjacent AChR (arrows) were observed in the biglycan null junctions. Scale bar, 10 μm. B, Quantification of the number of synapses with aligned or misaligned AChR and AChE in wild-type and biglycan null muscles. In wild-type muscle complete alignment was observed at 100% (90/90) of synapses. However, only 20% of the mutant synapses (30/150) showed complete alignment. n = number of synapses scored for each genotype.