Nematode-Trapping Fungi and Caenorhabditis elegans as a Model System for Predator–Prey Interactions

All habitats on earth host various sympatric organisms that interact in different ways. Predator–prey dynamics represent one such mode of interaction, which are shaped by coevolution of the interacting organisms, resulting in complex signal exchanges and eliciting a diversity of hunting and escape strategies. A predatory lifestyle has evolved independently in major phyla of the fungal kingdom. These carnivorous fungi use diverse strategies to hunt fast-moving nematodes, and they are of particular interest due to their potential as biocontrol agents against parasitic nematodes. The fascinating biology of carnivorous fungi has interested scientists for decades. Over the past few years, significant progress has been made in understanding the molecular mechanisms underlying predation by nematode-trapping fungi. Given the extensive research tools and resources that are available for the model nematode Caenorhabditis elegans, the microscopic fungal–nematode predator–prey system represents an exceptional model for exploring coevolution and predator–prey dynamics. Herein, we summarize the current knowledge of the predator–prey interactions between nematode-trapping fungi and C. elegans, focusing on the predation process and the molecular mechanisms underlying it. We envision that, given recent advances in experimental techniques developed for nematode-trapping fungi, scientists will continue to unravel how these carnivorous fungi have coevolved with their nematode prey.