title: Transgenic mimicry of pathogen attack stimulates growth and secondary metabolite accumulation.
abstract: Plant secondary metabolites, including pharmaceuticals, flavorings and aromas, are often produced in response to stress. We used chemical inducers of the pathogen defense response (jasmonic acid, salicylate, killed fungi, oligosaccharides and the fungal elicitor protein, cryptogein) to increase metabolite and biomass production in transformed root cultures of the medicinal plant, Withania somnifera, and the weed, Convolvulus sepium. In an effort to genetically mimic the observed effects of cryptogein, we employed Agrobacterium rhizogenes to insert a synthetic gene encoding cryptogein into the roots of C. sepium, W. somnifera and Tylophora tanakae. This genetic transformation was associated with stimulation in both secondary metabolite production and growth in the first two species, and in growth in the third. In whole plants of Convolvulus arvensis and Arabidopsis thaliana, transformation with the cryptogein gene led, respectively, to increases in the calystegines and certain flavonoids. A similar transgenic mimicry of pathogen attack was previously employed to stimulate resistance to the pathogen and abiotic stress. In the present study of biochemical phenotype, we show that transgenic mimicry is correlated with increased secondary metabolite production in transformed root cultures and whole plants. We propose that natural transformation with genes encoding the production of microbial elicitors could influence interactions between plants and other organisms.
authors.affiliation: Department of Botany, University of Calcutta, Calcutta, 700019, India.
authors.forename: Kuntal
authors.initials: K
authors.lastname: Chaudhuri
authors.forename: Sudripta
authors.initials: S
authors.lastname: Das
authors.forename: Moumita
authors.initials: M
authors.lastname: Bandyopadhyay
authors.forename: Andreja
authors.initials: A
authors.lastname: Zalar
authors.forename: Albert
authors.initials: A
authors.lastname: Kollmann
authors.forename: Sumita
authors.initials: S
authors.lastname: Jha
authors.forename: David
authors.initials: D
authors.lastname: Tepfer
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics / Q000472:pathogenicity*; D020418:Algal Proteins / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development; D031254:Convolvulus / Q000235:genetics / Q000254:growth & development; D005419:Flavonoids / Q000378:metabolism; D005656:Fungal Proteins; D010935:Plant Diseases; D018517:Plant Roots / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development; D010946:Plants, Medicinal / Q000235:genetics / Q000254:growth & development*; D014170:Transformation, Genetic; D014326:Tropanes / Q000378:metabolism*; D031110:Tylophora / Q000235:genetics / Q000254:growth & development; D032341:Withania / Q000235:genetics / Q000254:growth & development
chemical_list: D020418:Algal Proteins; D005419:Flavonoids; D005656:Fungal Proteins; D014326:Tropanes; C055033:calystegin; C061032:cryptogein protein, Phytophthora cryptogea