Axon termination of the SAB motor neurons in <i>C. elegans</i> depends on pre- and postsynaptic activity.

ABSTRACT: Axon termination is a critical step in neural circuit formation, but the contribution of activity from postsynaptic targets to this process remains unclear. Using Caenorhabditis elegans SAB neurons as a model system, we showed that inhibition of muscle activity during a critical period of postembryonic development led to axonal overgrowth and ectopic synapse formation. This effect is mediated by a local retrograde signal and requires neuronal voltage-gated calcium channels (VGCCs) acting cell-autonomously to constrain axon growth. Manipulating SAB neuron excitability demonstrated that increased intrinsic neuronal activity drives overgrowth, while reducing activity suppresses it, establishing a functional link between muscle-derived cues and presynaptic excitability. Transcriptomic a

SUBMITTER: Weinreb A 

PROVIDER: S-EPMC12439959 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature