MUSK and Fatigable weakness: Recently, a monoclonal MuSK antibody was shown to stimulate MuSK phosphorylation and to preserve NMJs in a motor neuron disease model.23 Using new or repurposed drugs to enhance MuSK phosphorylation, or other downstream components of the signaling pathway, could be beneficial in MuSK-Ab myasthenia and perhaps in other disorders of neuromuscular transmission where loss of AChRs or disruption of the NMJ structure underlies the muscle weakness.