The image shows C. elegans expressing the molecular motor UNC-104/KIF1A (kinesin-3). The motor is specifically expressed in the nervous system of the worm and is the major transporter of synaptic vesicles. Single nerves and soma can be identified in the worm while strong expression of the motor occurs in the brain. Recently, we reported a regulatory function of the multifunctional active zone protein SYD-2/liprin-α on UNC-104/KIF1A (Wagner et al., PNAS, 2009). It seems that SYD-2 is not only a cargo for UNC-104 but also regulates speed and directionality of the motor. Moreover, the scaffolding function of SYD-2 promotes the formation of motor-clusters along the neuronal projections. The latter might be important for cargo-trafficking in the lengthy C. elegans neurons while we propose a model in which inactive motors are exchanged by active ones at sites of motor-clusters.