Molecular insights into volatile organic compound sensing and signaling in plants

Plants interact with their surrounding environment through the perception of a vast and structurally diverse array of volatile organic compounds (VOCs); however, the molecular mechanisms involved remain mostly unknown. Despite the large number of VOCs emitted and perceived by plants, only a small number of phylogenetically distinct, but often structurally similar receptors and receptor-like proteins have been identified and characterized to date. In this review, we summarize the current knowledge on plant VOC perception, with an emphasis on the receptors involved, including their structural characteristics and ligand specificities, as well as how distinct VOC signals can be translated into different downstream physiological responses. We further highlight the involvement of KARRIKIN INSENSITIVE 2 (KAI2)-mediated signaling in the perception of volatile compounds and their derivatives, discussing its potential role in expanding the repertoire of plant VOC perception mechanisms.