Arabidopsis Proline Dehydrogenase Contributes to Flagellin-Mediated PAMP-Triggered Immunity by Affecting RBOHD.
Plants activate different defense systems to counteract the attack of microbial pathogens. Among them, the recognition of conserved microbial- or pathogen-associated molecular patterns (MAMPs or PAMPs) by pattern-recognition receptors stimulates MAMP- or PAMP-triggered immunity (PTI). In recent years, the elicitors, receptors, and signaling pathways leading to PTI have been extensively studied. However, the contribution of organelles to this program deserves further characterization. Here, we studied how processes altering the mitochondrial electron transport chain (mETC) influence PTI establishment. With particular emphasis, we evaluated the effect of proline dehydrogenase (ProDH), an enzyme that can load electrons into the mETC and regulate the cellular redox state. We found that mETC uncouplers (antimycin or rotenone) and manganese superoxide dismutase deficiency impair flg22-induced responses such as accumulation of reactive oxygen species (ROS) and bacterial growth limitation. ProDH mutants also reduce these defenses, decreasing callose deposition as well. Using ProDH inhibitors and ProDH inducers (exogenous Pro treatment), we showed that this enzyme modulates the generation of ROS by the plasma membrane respiratory burst NADPH oxidase homolog D. In this way, we contribute to the understanding of mitochondrial activities influencing early and late PTI responses and the coordination of the redox-associated mitochondrial enzyme ProDH with defense events initiated at the plasma membrane.
Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina.
Georgina
G
Fabro
Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina.
Yanina Soledad
YS
Rizzi
Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC, CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina.
María Elena
ME
Alvarez
D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005408:Flagellin / Q000378:metabolism; D005936:Glucans / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000378:metabolism; D057865:Plant Immunity; D011394:Proline Oxidase / Q000235:genetics / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D051192:Receptors, Pattern Recognition / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D005936:Glucans; D000069452:Pathogen-Associated Molecular Pattern Molecules; D017382:Reactive Oxygen Species; D051192:Receptors, Pattern Recognition; D005408:Flagellin; C048306:callose; D011394:Proline Oxidase; C568857:AT5G47910 protein, Arabidopsis; D019255:NADPH Oxidases; C022709:superoxide-forming enzyme; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis