Protein Tyrosine Phosphatase Receptor Type R (PTPRR) Reduces AChR Clustering by Dephosphorylating MuSK

Figure 1

C2C12 myotubes provide an excellent experimental model system for studying agrin-induced acetylcholine receptor (AChR) clustering. (a) Wild-type C2C12 myotubes were incubated with increasing concentrations of agrin (0 to 20 ng/ml) for 24 h, and AChRs were labeled with Alexa Fluor 555 α-bungarotoxin. AChR clustering increased with increasing agrin concentrations (0 to 10 ng/ml). C2C12 myotubes treated with 10 ng/ml and 20 ng/ml agrin did not demonstrate a significant difference. White arrowheads indicate AChR clusters. (b) Quantification of AChR clusters ≥5 μm in length from Figure 1. The average length of each AChR cluster and the average number of AChR clusters within a 1 mm tube were quantified. The data were obtained from at least three experiments. Data were shown as .

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