title: Piriformospora indica confers drought tolerance in Chinese cabbage leaves by stimulating antioxidant enzymes, the expression of drought-related genes and the plastid-localized CAS protein.
abstract: Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance against biotic and abiotic stress. The fungus strongly colonizes the roots of Chinese cabbage, promotes root and shoot growth, and promotes lateral root formation. When colonized plants were exposed to polyethylene glycol to mimic drought stress, the activities of peroxidases, catalases and superoxide dismutases in the leaves were upregulated within 24h. The fungus retarded the drought-induced decline in the photosynthetic efficiency and the degradation of chlorophylls and thylakoid proteins. The expression levels of the drought-related genes DREB2A, CBL1, ANAC072 and RD29A were upregulated in the drought-stressed leaves of colonized plants. Furthermore, the CAS mRNA level for the thylakoid membrane associated Ca(2+)-sensing regulator and the amount of the CAS protein increased. We conclude that antioxidant enzyme activities, drought-related genes and CAS are three crucial targets of P. indica in Chinese cabbage leaves during the establishment of drought tolerance. P. indica-colonized Chinese cabbage provides a good model system to study root-to-shoot communication.
authors.affiliation: Institute of Plant Physiology, Friedrich-Schiller-University Jena, Jena, Germany.
authors.forename: Chao
authors.initials: C
authors.lastname: Sun
authors.forename: Joy M
authors.initials: JM
authors.lastname: Johnson
authors.forename: Daguang
authors.initials: D
authors.lastname: Cai
authors.forename: Irena
authors.initials: I
authors.lastname: Sherameti
authors.forename: Ralf
authors.initials: R
authors.lastname: Oelmüller
authors.forename: Binggan
authors.initials: B
authors.lastname: Lou
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D000975:Antioxidants / Q000378:metabolism; D001487:Basidiomycota / Q000187:drug effects / Q000502:physiology*; D015415:Biomarkers / Q000378:metabolism; D018533:Biomass; D001937:Brassica / Q000166:cytology / Q000201:enzymology / Q000235:genetics* / Q000382:microbiology; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002681:China; D015169:Colony Count, Microbial; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects / Q000235:genetics; D018515:Plant Leaves / Q000166:cytology / Q000201:enzymology / Q000235:genetics* / Q000382:microbiology; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000382:microbiology; D018087:Plastids / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011092:Polyethylene Glycols / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D002135:Calcium-Binding Proteins; D012333:RNA, Messenger; D011092:Polyethylene Glycols; D008315:Malondialdehyde