In association with pct-1, regulates the trafficking of synaptic vesicle precursors in DA motor neurons by promoting anterograde trafficking to the axon and preventing dynein-dependent trafficking to the dendrite. May also regulate synaptic vesicle trafficking in DD motor neurons and in RIA interneurons (PubMed:20510931). Involved in synapse formation during DD motor neuron remodeling by disassembling ventral presynaptic structures (PubMed:21609829). May activate cdk-5 (PubMed:20510931). Interacts with pct-1; the interaction is required to activate pct-1. Enriched in the dendrite and the proximal axon of the DA motor neuron. Abnormal localization of synaptic vesicle components and active zone proteins in the cell body and in the dentrite of DA9 motor neuron (PubMed:20510931). In L4 mutants, incomplete elimination of ventral rab-3-positive synaptic vesicles and small reduction in the formation of dorsal rab-3-positive synaptic vesicles in DD motor neurons, although formation of ventral synapses at the L1 stage is normal (PubMed:21609829). No other phenotype except a slightly smaller progeny size (PubMed:20510931). Belongs to the cyclin family.