Arbuscular mycorrhizal dialogues: do you speak 'plantish' or 'fungish'?

Plants rely on their associated microbiota for crucial physiological activities; realization of this interaction drives research to understand inter-domain communication. This opinion report focuses on the arbuscular mycorrhizal (AM) symbiosis, which involves the Glomeromycota, fungi that can form a symbiosis with most plants. We examine the hypothesis that the molecules involved in inter-kingdom symbiotic signaling, such as strigolactones, cutin monomers, and chitin-related molecules, also have key roles in development, originally unrelated to symbiosis. Thus, their symbiotic roles rely on the co-evolved capacity of the AM partners to perceive and interpret these molecules as symbiotic signals.