OBJECTIVE To identify the molecular basis of a fatal syndrome of microcephaly, cortical hyperexcitability, and myasthenia. METHODS We performed clinical and in vitro microelectrode studies of neuromuscular transmission, examined neuromuscular junctions cytochemically and by electron microscopy (EM), and searched for mutations by Sanger and exome sequencing. RESULTS Neuromuscular transmissio...

In cultured hippocampal neurons, synaptogenesis is largely independent of synaptic transmission, while several accounts in the literature indicate that synaptogenesis at cholinergic neuromuscular junctions in mammals appears to partially depend on synaptic activity. To systematically examine the role of synaptic activity in synaptogenesis at the neuromuscular junction, we investigated neuromusc...