Volatile communication in plants relies on a KAI2-mediated signaling pathway
Shannon A. Stirling, Angelica M. Guercio, Ryan M. Patrick, Xingqi Huang, Matthew E. Bergman, Varun Dwivedi, Ruy Kortbeek, Yi‐Kai Liu, Fuai Sun, W. Andy Tao, Ying Li, Benoît Boachon, Nitzan Shabek, Natalia Dudareva
Abstract
Plants are constantly exposed to volatile organic compounds (VOCs) that are released during plant-plant communication, within-plant self-signaling, and plant-microbe interactions. Therefore, understanding VOC perception and downstream signaling is vital for unraveling the mechanisms behind information exchange in plants, which remain largely unexplored. Using the hormone-like function of volatile terpenoids in reproductive organ development as a system with a visual marker for communication, we demonstrate that a petunia karrikin-insensitive receptor, PhKAI2ia, stereospecifically perceives the (-)-germacrene D signal, triggering a KAI2-mediated signaling cascade and affecting plant fitness. This study uncovers the role(s) of the intermediate clade of KAI2 receptors, illuminates the involvement of a KAI2ia-dependent signaling pathway in volatile communication, and provides new insights into plant olfaction and the long-standing question about the nature of potential endogenous KAI2 ligand(s).