Fungi have systems to sense and respond to plant signals, study suggests

CAMBRIDGE, Mass. — Yeast and other fungi normally live on the outside of a plant, a nutrient-poor environment. Microorganisms can utilize wounds as opportunity for infection, thereby gaining access to the nutrient rich environment inside the plant. Just how fungi identify a wound on a plant, though, is a mystery.

Research published in the latest issue of the journal Proceedings of the National Academy of Sciences suggests that fungi have developed systems to sense and respond to specific signals produced by a host plant. Specifically, fungi living outside a plant perceive the presence of a hormone called indole 3-acetic acid (IAA) and may use it as a signal of a potential wound site. The scientists suspect that the fungi then switch from a benign yeast to a pathogenic form and infect the plant.

The ability of a fungus to perceive a plant hormone and differentiate into an invasive form has important implications for plant-pathogen interactions, according to Reeta Prusty, lead author of this new study and postdoctoral scientist in the lab of Whitehead Member and MIT professor Gerald Fink.

Citation

Prusty, R., Grisafi, P., & Fink, G. R. (2004). The plant hormone indoleacetic acid induces invasive growth in Saccharomyces cerevisiae. Proceedings of the National Academy of Sciences, 101(12), 4153-4157.