Plant response to misfolded protein in the cytosol

Virus infection and over expression of protein in cytosol induce a subset of HSP70s. We named this response the Cytosolic Protein Response (CPR) and have been investigating it in the context of a parallel mechanism in the soluble cytosol with the UPR, and as a subcomponent of the larger HS response. This experiment was carried out to study the transcriptional aspect of CPR. In this analysis, we have triggered CPR by infiltrating proline analogue, L-azetidine-2-carboxylic acid (AZC) into Arabidopsis mature leaves. Since AZC trigger unfolded protein response(UPR) in ER as well as CPR, we have included tunicamycin treatment, which is a specific inducer of UPR to subtract the effect of UPR from the AZC response. Heat shocked samples were included to identify CPR as a subcomponent of larger HS response. We used microarray data to identify the genes upregurated by CPR. These genes were commonly upregulated by AZC and HS but not by tunicamycin treatment. Keywords: stress response Arabidopsis mature leaves were infiltrated with AZC or L-Proline (control of AZC) and tunicamycin or DMF(solvent control of tunicamycin). For the heat shock treatment, six mature leaves were detached from plant and incubated at 37 °C or 20°C (as a control) for a period of 1h. The experiment was repeated three times for AZC and HS treatment (3 biological replication). Tunicamycin experiment was repeated five times due to large valiation in the responses (5 biological replication).