A cilia-mediated environmental input induces solitary behaviour in Caenorhabditis elegans and Pristionchus pacificus nematodes

Nematodes respond to a multitude of environmental cues. For example, the social behaviours clumping and bordering were described as a mechanism of hyperoxia avoidance inCaenorhabditis elegansandPristionchus pacificus. A recent study inP. pacificusrevealed a novel regulatory pathway that inhibits social behaviour in a response to an as yet unknown environmental cue. This environmental signal is recognised by ciliated neurons, as mutants defective in intraflagellar transport (IFT) proteins display social behaviours. The IFT machinery represents a large protein complex and many mutants in genes encoding IFT proteins are available inC. elegans. However, social phenotypes inC. elegansIFT mutants have never been reported. Here, we examined 15 previously isolatedC. elegansIFT mutants and found that most of them showed strong social behaviour. These findings indicate conservation in the inhibitory mechanism of social behaviour betweenP. pacificusandC. elegans.