Abstract

Brains are highly parallel information processors. Neural circuits continuously integrate sensory inputs to generate appropriate behavioural responses. C. elegans only have 302 neurons whose connectivity is perfectly known, providing the entire wiring diagram of the worm nervous system. By combining genetic, neuronal activity imaging techniques and optogenetic tools we can dissect how these circuits work in response to sensory cues. A particular focus is on neuropeptides. Neuropeptides are potent regulators of behaviour but their biology is poorly understood. As C.elegans is transparent, GFP -tagged neuropeptides can be followed through the secretory pathway and forward or reverse genetics used to identify mutants that disrupt production, traffic and release of neuropeptide. We identify several new regulators of neuropeptide biology and mechanisms allowing proper distribution of the vesicles containing the neuropeptide. Neural signalling components are well-conserved between C. elegans and vertebrates, so the results obtained in the nematode are likely to be directly applicable to the mammalian nervous system.