Virulence genes of the phytopathogen Rhodococcus fascians show specific spatial and temporal expression patterns during plant infection

• Published in: Molecular plant-microbe interactions Vol. 15; no. 4; pp. 398 - 403
• Main Authors: CORNELIS, Karen, MAES, Tania, JAZIRI, Mondher, HOLSTERS, Marcelle, GOETHALS, Koen
• Format: Journal Article
• Language: English
• Published: St Paul, MN APS Press 01.04.2002; The American Phytopathological Society
• Subjects: att gene; Bacterial plant pathogens; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biological and medical sciences; Colony Count, Microbial; fas gene; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Bacterial; Glucuronidase - genetics; Glucuronidase - metabolism; GUS fusion; histochemical analysis; Nicotiana - genetics; Nicotiana - microbiology; Pathology. Damages, economic importance; Phytopathology. Animal pests. Plant and forest protection; Plant Diseases - microbiology; Plant Leaves - microbiology; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Rhodococcus - genetics; Rhodococcus - metabolism; Rhodococcus - pathogenicity; Rhodococcus fascians; Virulence - genetics; Plant pathogen; Tissue specificity; Stimulant plant; Host agent relation; Rhodococcus fascians; Gene expression; Nicotiana tabacum; Spatial variation; Time variation; Meristem; Infection; Pathogenicity; Regulation(control); Penetration; Dicotyledones; Angiospermae; Virulent strain; Bacteria; Actinomycetes; Spermatophyta; Solanaceae; Colonization; Histochemistry
• ISSN: 0894-0282; 1943-7706
• DOI: 10.1094/MPMI.2002.15.4.398

The phytopathogenic bacterium Rhodococcus fascians provokes shoot meristem formation and malformations on aerial plant parts, mainly at the axils. The interaction is accompanied by bacterial colonization of the plant surface and tissues. Upon infection, the two bacterial loci required for full virulence, fas and att, were expressed only at the sites of symptom development, although their expression profiles differed both spatially and temporally. The att locus was expressed principally in bacteria located on the plant surface at early stages of infection. Expression of the fas locus occurred throughout infection, mainly in bacteria that were penetrating, or had penetrated, the plant tissues and coincided with sites of meristem initiation and proliferation. The implications for the regulation of virulence genes of R. fascians during plant infection are discussed.