E-NASC-5 - The role of the OX1 protein kinase in H2O2 signal transduction
Released on 21 October 2003, last updated on 22 November 2011
Expression of the OX1 gene coding for a putative protein kinase was shown to be induced in Arabidopsis thaliana ecotypes Col-0, WS and RLD seedlings by treatment with H2O2 superoxidecolddroughtsalt and cellulase (elicitor). All of these treatments will ultimately lead to production of H2O2 either as a secondary effect of the applied stress through disturbance of electron transport processes or as a direct product of the plant NADPH oxidases (oxidative burst). However the sets of protective genes switched on (end-responses) will differ depending on the original stress. The induction characteristics of OX1 point to a role of this kinase in signal transduction downstream of H2O2; however it is not clear which primary signal is relayed. OX1 may function in the perception of oxidative stress caused by all/any one of the environmental stresses and/or it may be important in signalling downstream of the oxidative burst triggered by pathogen infection and wounding. An OX1 knock-out was isolated from the Wisconsin T-DNA lines with an insertion between the first and second conserved kinase domains rendering the protein product non-functional. Aim of the microarray experiment is to compare gene induction in the homozygous knock-out line to that in the wild-type (ecotype WS) following H2O2 treatment. To this end 7 day-old seedlings will be immersed in 10 mM solution for 1 h. Analysis of differences in expression of genes belonging to a certain end-response will disclose the signalling pathway which OX1 functions in. This is necessary for further planned experiments e.g. analysis of inducible OX1 antisense and constitutive lines as well as kinase activity assays.
transcription profiling by array