Localized expression of the gene in rice roots on infection of arbuscular mycorrhizal fungus and hydrolysis of -GR24 by the encoded protein.

Strigolactones (SLs) are plant hormones that control diverse aspects of the shoot and root growth and are exuded into the soil as recruitment signals for arbuscular mycorrhizal (AM) fungi. SL signaling in plants is transduced the α/β-hydrolase receptor Dwarf14 (D14). The D14 family consists of D14, Dwarf14-like (D14L), and Dwarf14-like 2 (D14L2) clades in rice. The D14L receptor is known to condition pre-symbiotic perception of AM fungi. In this study, it was found that the () gene expression was significantly induced by AM fungal colonization. The transcript of appeared not only in mature arbuscule-containing cells but also in epidermal/cortical cells at an early colonization stage and near the elongating intercellular hyphae. transcript was detected normally in mycorrhizal roots of mutant that form stunted arbuscules, suggesting that the gene expression is independent of arbuscule development. Moreover, the recombinant D14L2a protein exhibited hydrolase activity of synthetic SL, -GR24. Based on these results, we discussed the role of D14L2 in the establishment of AM symbiosis.