Transcription in neuromuscular junction formation: who turns on whom?

The neuromuscular junction is a particular advantageous synapse to investigate the molecular processes engaged in synaptogenesis. Both the motor nerve and the muscle cell contribute to the patterned distribution of a definite set of membrane proteins into two distinct regions, a sub-synaptic end plate zone and an extra-synaptic region. Accordingly, the transcription of acetylcholine receptors is highly compartmentalized being much higher in the sub-synaptic the in the extra-synaptic region. In this review, we focus on the signaling pathways and the gene expression mechanisms that mediate the enhanced transcription in the sub-synaptic region and the silencing of transcription in extra-synaptic regions.