Tobacco cells contain a protein, immunologically related to the neutrophil small G protein Rac2 and involved in elicitor-induced oxidative burst.
Suspension-cultured cells of Nicotiana tabacum generated active oxygen species (AOS) when they were treated with the proteinaceous elicitor, cryptogein. This response was blocked by diphenylene iodonium, an inhibitor of the neutrophil NADPH oxidase. When microsomal extracts of tobacco cells were probed with an antibody directed against the human small G protein Rac2, two immunoreactive proteins were detected at 18.5 and 20.5 kDa. The same experiment performed with cytosolic extracts of tobacco cells led to the observation of a strong immunoreactive protein at 21.5 kDa only in the cryptogein-treated cells. The appearance of this cytosolic protein was related to the production of AOS by the elicited cells. These results provide evidence for the possible involvement of small G proteins, homologous to the neutrophil Rac2 protein, in the regulation of the elicitor-induced oxidative burst in plant.
Kieffer
F
F
Unité associée INRA/Université de Bourgogne 692, Laboratoire de Phytoipharmacie et de Biochimie des Interactions Cellulaire, Dijon, France.
Simon-Plas
F
F
Maume
B F
BF
Blein
J P
JP
D020418:Algal Proteins; D015153:Blotting, Western; D002478:Cells, Cultured; D005656:Fungal Proteins / Q000494:pharmacology*; D019204:GTP-Binding Proteins / Q000276:immunology*; D010947:Plants, Toxic; D017382:Reactive Oxygen Species; D016897:Respiratory Burst; D014026:Nicotiana / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D020744:rac GTP-Binding Proteins
D020418:Algal Proteins; D005656:Fungal Proteins; D017382:Reactive Oxygen Species; C061032:cryptogein protein, Phytophthora cryptogea; D019204:GTP-Binding Proteins; D020744:rac GTP-Binding Proteins