A novel Arabidopsis-Colletotrichum pathosystem for the molecular dissection of plant-fungal interactions.
The ability of a Colletotrichum sp., originally isolated from Brassica campestris, to infect Arabidopsis thaliana was examined. Sequence analysis of the internal transcribed spacer (ITS)1, 5.8S RNA gene and ITS2 regions of ribosomal (r)DNA showed the pathogen to be Colletotrichum destructivum. The host range was broad, including many cruciferous plants and some legumes. At 25 degrees C, all A. thaliana accessions tested were susceptible to the Brassica isolates of C. destructivum; however, at 15 degrees C, the accession Ws-2 showed a temperature-dependant resistance, in which single epidermal cells underwent a rapid hypersensitive response. Legume isolates of C. destructivum were unable to infect A. thaliana and induced deposition of callose papillae at sites of attempted penetration. In compatible interactions, C. destructivum showed a two-stage, hemibiotrophic infection process. The initial biotrophic phase was associated with large, intracellular primary hyphae and was confined to one epidermal cell; whereas, in the subsequent necrotrophic phase, narrow secondary hyphae extensively colonized the tissue and conidia were produced in acervuli. An efficient transformation system was established for C. destructivum, using Agrobacterium-mediated transfer of DNA. The ability to genetically manipulate both partners in the interaction is an important advantage, and the Arabidopsis-Colletotrichum pathosystem should provide a valuable new model for dissecting plant-fungal interactions.
O'Connell
Richard
R
UMR 5546, CNRS-Université Paul Sabatier, Pôle de Biotechnologie Végétale, 24 Chemin de Borde Rouge, BP17 Auzeville, 31326 Castanet-Tolosan, France. oconnel@smcv.ups-tlse.fr
Herbert
Corentin
C
Sreenivasaprasad
Surapareddy
S
Khatib
Moustafa
M
Esquerré-Tugayé
Marie-Thérèse
MT
Dumas
Bernard
B
D017360:Arabidopsis / Q000235:genetics* / Q000382:microbiology / Q000648:ultrastructure; D001483:Base Sequence; D020231:Colletotrichum / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics; D007113:Immunity, Innate / Q000235:genetics; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics; D012231:Rhizobium / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D013696:Temperature; D014170:Transformation, Genetic
D021903:DNA, Ribosomal Spacer; D005656:Fungal Proteins; D012340:RNA, Ribosomal, 5.8S