Gene expression during innate immunity in tobacco triggered by bacteria.

ABSTRACT: To study basal resistance we inoculated tobacco plants with Pseudomonas syringae pv. syringae 61 hrcC mutants (gift of A. Collmer). To compare the expression profiles of basal resistance to hypersensitive response, we used P. syringae pv. syringae 61. Gene activation triggered by the live compatible pathogen P. syringae pv. tabaci was compared to kanamycine-inactivated P. tabaci (10 min in 100 ug/ml KM, then washed 2x in H2O). Water-infiltrated control leaves were used. The aim of another set of experiments was to investigate the influence of various signal transduction pathways on basal resistance. Control plants were infiltrated with P. syringae pv syringae hrcC mutant bacteria. These were compared to treatments, in which the bacterial suspensions were supplemented with inhibitors that can block a specific type of signal transduction pathway. The inhibitors represented Ca2+ signaling, lipid derived signals generated by phospholipase C and A, protein phosphorilation (kinases) and protein degradation (degradation of transcription repressors or activators). The used inhibitors were LaCl3, neomycin, aristolochic acid, K252a and MG115 respectively. 2-2.5 months old tobacco plants (Nicotiana tabacum cv. Samsun nn) were grown in a greenhouse in soil with cca. 16/8 hr light/dark period at 20°C, then in a growth chamber 2 days before and during experiments, under identical conditions. A syringe was used for the injection of bacteria or chemical solutions into the tobacco leaves. At 6 or 48 hours post inoculation, leaf samples were taken, and frozen in liquid nitrogen. Every experiment was carried out in 3 independent replicates. Total RNA was extracted using the Quiagen RNeasy Plant Mini kit and the Quiagen Rnase-free Dnase Set, then re-purified and concentrated on Microcon-30 (Millipore) columns. The concentration and quality of isolated RNA was estimated by measuring its absorbency at 260 and 280 nm and running on 1% agarose gel. Keywords: Direct comparison

ORGANISM(S): Nicotiana langsdorffii x Nicotiana sanderae Solanum tuberosum Nicotiana tabacum

PROVIDER: GSE10482 | GEO | 2008/02/13

SECONDARY ACCESSION(S): PRJNA107927

REPOSITORIES: GEO