MicroRNAs (miRNAs) play important roles in plant physiological activities. However, their roles and molecular mechanisms in boosting plant immunity, especially through the modulation of macronutrient metabolism in res...MicroRNAs (miRNAs) play important roles in plant physiological activities. However, their roles and molecular mechanisms in boosting plant immunity, especially through the modulation of macronutrient metabolism in response to pathogens, are largely unknown. Here, we report that an evolutionarily conserved miRNA, miR395, promotes resistance to Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc), two destructive bacterial pathogens, by regulating sulfate accumulation and distribution in rice. Specifically, miR395 targets and suppresses the expression of the ATP sulfurylase gene OsAPS1, which functions in sulfate assimilation, and two sulfate transporter genes, OsSULTR2;1 and OsSULTR2;2, which function in sulfate translocation, to promote sulfate accumulation, resulting in broad-spectrum resistance to bacterial pathogens in miR395-overexpressing plants. Genetic analysis revealed that miR395-triggered resistance is involved in both pathogen-associated molecular pattern-triggered immunity and R gene-mediated resistance. Moreover, we found that accumulated sulfate but not S-metabolites inhibits proliferation of pathogenic bacteria, revealing a sulfate-mediated antibacterial defense mechanism that differs from sulfur-induced resistance. Furthermore, compared with other bacteria, Xoo and Xoc, which lack the sulfate transporter CysZ, are sensitive to high levels of extracellular sulfate. Accordingly, miR395-regulated sulfate accumulation impaired the virulence of Xoo and Xoc by decreasing extracellular polysaccharide production and biofilm formation. Taken together, these results suggest that rice miR395 modulates sulfate metabolism to exploit pathogen sensitivity to sulfate and thereby promotes broad-spectrum resistance.展开更多
基金supported by grants from the National Natural Science Foundation of China(31821005,31822042,and 31871946)the National Science Foundation of Hubei Province(2020CFA058)the Fundamental Research Funds for the Central Universities(2662019FW006).
文摘MicroRNAs (miRNAs) play important roles in plant physiological activities. However, their roles and molecular mechanisms in boosting plant immunity, especially through the modulation of macronutrient metabolism in response to pathogens, are largely unknown. Here, we report that an evolutionarily conserved miRNA, miR395, promotes resistance to Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc), two destructive bacterial pathogens, by regulating sulfate accumulation and distribution in rice. Specifically, miR395 targets and suppresses the expression of the ATP sulfurylase gene OsAPS1, which functions in sulfate assimilation, and two sulfate transporter genes, OsSULTR2;1 and OsSULTR2;2, which function in sulfate translocation, to promote sulfate accumulation, resulting in broad-spectrum resistance to bacterial pathogens in miR395-overexpressing plants. Genetic analysis revealed that miR395-triggered resistance is involved in both pathogen-associated molecular pattern-triggered immunity and R gene-mediated resistance. Moreover, we found that accumulated sulfate but not S-metabolites inhibits proliferation of pathogenic bacteria, revealing a sulfate-mediated antibacterial defense mechanism that differs from sulfur-induced resistance. Furthermore, compared with other bacteria, Xoo and Xoc, which lack the sulfate transporter CysZ, are sensitive to high levels of extracellular sulfate. Accordingly, miR395-regulated sulfate accumulation impaired the virulence of Xoo and Xoc by decreasing extracellular polysaccharide production and biofilm formation. Taken together, these results suggest that rice miR395 modulates sulfate metabolism to exploit pathogen sensitivity to sulfate and thereby promotes broad-spectrum resistance.
