부산대학교 도서관

SUMMARY: Plant roots release phytochemicals into the soil environment to influence nutrient availability and uptake. Arabidopsis thaliana roots release phenylpropanoid coumarins in response to iron (Fe) deficiency, likely to enhance Fe uptake and improve plant health. This response requires sufficient phosphorus (P) in the root environment. Nonetheless, the regulatory interplay influencing coumarin production under varying availabilities of Fe and P is not known. Through genome‐wide association studies, we have pinpointed the influence of the ABC transporter G family member, PDR9, on coumarin accumulation and trafficking (homeostasis) under combined Fe and P deficiency. We show that genetic variation in the promoter of PDR9 regulates its expression in a manner associated with coumarin production. Furthermore, we find that MYB63 transcription factor controls dedicated coumarin production by regulating both COUMARIN SYNTHASE (COSY) and FERULOYL‐CoA 6′‐HYDROXYLASE 1 (F6′H1) expression while orchestrating secretion through PDR9 genes under Fe and P combined deficiency. This integrated approach illuminates the intricate connections between nutrient signaling pathways in coumarin response mechanisms. Significance Statement: Plant roots release phenylpropanoid coumarins in response to iron deficiency, potentially enhancing iron uptake. Influenced by phosphorus levels, the regulatory dynamics of coumarin biosynthesis and transport are unknown. Our studies reveal the ABC transporter G family member, PDR9, influences coumarin homeostasis under combined iron and phosphorus deficiency. Genetic variations in PDR9's promoter control its expression, impacting coumarin secretion. The MYB63 transcription factor orchestrates coumarin biosynthesis, linking nutrient signaling pathways in coumarins response mechanisms. [ABSTRACT FROM AUTHOR]