Impact of arbuscular mycorrhizal fungi on the allergenic potential of tomato.
Arbuscular mycorrhizal (AM) fungi influence the expression of defence-related genes in roots and can cause systemic resistance in plants probably due to the induced expression of specific defence proteins. Among the different groups of defence proteins, plant food allergens were identified. We hypothesized that tomato-allergic patients differently react to tomatoes derived from plants inoculated or not by mycorrhizal fungi. To test this, two tomato genotypes, wild-type 76R and a nearly isogenic mycorrhizal mutant RMC, were inoculated with the AM fungus Glomus mosseae or not under conditions similar to horticultural practice. Under such conditions, the AM fungus showed only a very low colonisation rate, but still was able to increase shoot growth of the wild-type 76R. Nearly no colonisation was observed in the mutant RMC, and shoot development was also not affected. Root fresh weights were diminished in AM-inoculated plants of both genotypes compared to the corresponding controls. No mycorrhizal effects were observed on the biomass and the concentration of phosphate and nitrogen in fruits. Real-time quantitative polymerase chain reaction analysis revealed that six among eight genes encoding for putative allergens showed a significant induced RNA accumulation in fruits of AM-colonised plants. However, human skin reactivity tests using mixed samples of tomato fruits from the AM-inoculated and control plants showed no differences. Our data indicate that AM colonisation under conditions close to horticultural practice can induce the expression of allergen-encoding genes in fruits, but this does not lead necessarily to a higher allergenic potential.
Leibniz-Institute of Vegetable and Ornamental Crops, Großbeeren/Erfurt e.V., Theodor Echtermeyer Weg, 14979, Grossbeeren, Germany. schwarz@igzev.de.
Dietmar
D
Schwarz
Leibniz-Institute of Vegetable and Ornamental Crops, Großbeeren/Erfurt e.V., Theodor Echtermeyer Weg, 14979, Grossbeeren, Germany.
Saskia
S
Welter
Leibniz-Institute of Vegetable and Ornamental Crops, Großbeeren/Erfurt e.V., Theodor Echtermeyer Weg, 14979, Grossbeeren, Germany.
Eckhard
E
George
Leibniz-Institute of Vegetable and Ornamental Crops, Großbeeren/Erfurt e.V., Theodor Echtermeyer Weg, 14979, Grossbeeren, Germany.
Philipp
P
Franken
Proteome Factory AG, Magnusstr. 11, 12489, Berlin, Germany.
Karola
K
Lehmann
Department Molecular Systems Biology, Faculty of Life Science, University of Vienna, Althanstr. 14, 1090, Vienna, Austria.
Wolfram
W
Weckwerth
Department of Dermatology and Allergology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
Sabine
S
Dölle
Department of Dermatology and Allergology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
Margitta
M
Worm
D000328:Adult; D052179:Antigens, Plant / Q000235:genetics / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D005638:Fruit / Q000235:genetics / Q000254:growth & development / Q000276:immunology / Q000382:microbiology; D018506:Gene Expression Regulation, Plant; D055137:Glomeromycota / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D006801:Humans; D066298:In Vitro Techniques; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development / Q000276:immunology* / Q000382:microbiology*; D008297:Male; D038821:Mycorrhizae / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D055815:Young Adult
D052179:Antigens, Plant