Colonization of Mutualistic Mycorrhizal and Parasitic Blast Fungi Requires OsRAM2-Regulated Fatty Acid Biosynthesis in Rice.

Arbuscular mycorrhizal (AM) fungi form a mutual association with the majority of land plants, including most angiosperms of the dicotyledon and monocotyledon lineages. The symbiosis is based upon bidirectional nutrient exchange between the host and symbiont that occurs between inner cortical cells of the root and branched AM hyphae called arbuscules that develop within these cells. Lipid transport and its regulation during the symbiosis have been intensively investigated in dicotyledon plants, especially legumes. Here, we characterize and , homologs of and found that plants defective in were unable to be colonized by AM fungi and showed impaired colonization by . The induction of and is dependent on and the common symbiosis signaling pathway pathway genes and , while overexpression of results in increased expression of and . Collectively, our data show that the function and regulation of is conserved in monocot and dicot plants and reveals that, similar to mutualistic fungi, pathogenic fungi have recruited RAM2-mediated fatty acid biosynthesis to facilitate invasion.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.