Work Packages


Supervisory Board

Visiting Researcher








Project title: Redox regulation of chloroplast protein turnover

Objectives: This ESR is to study the role of cellular redox state in the control of chloroplast protein turnover

Description of work: ESR9 will determine the interactions between cellular redox state, proteinases and proteinase inhibitors in the control of leaf protein turnover in wild type and transgenic plants, and in mutants provided by other partners. ESR9 will characterize the changes in cellular redox state that occur during leaf development using various parameters such as determination of protein carbonyl groups, glutathionylation, and measurements of reactive oxygen species (ROS), NADP/NADPH ratios, reduced glutathione (GSH)/glutathione disulphide (GSSG), ascorbate/dehydroascorbate. ESR9 will characterise the expression patterns of proteinases and proteinase inhibitors induced during leaf senescence, particularly those that are differentially expressed in mutants (autophagy; HvWhirly; HvSV40; WP2; ESR6). ESR9 will produce transgenic plants constitutively expressing different types of proteinase inhibitor in chloroplasts. In the first instance, focus will be given to orzacystatin I (OCI) and maize serpin and Bowman Birk-type serine proteinase inhibitors but as the work progresses the functions of other proteinase inhibitors identified by other partners will be tested in transgenic plants. ESR9 will characterize the effects of these inhibitors on chloroplast protein turnover and leaf senescence in wild type and transgenic plants under optimal and stress conditions.

Deliverables: Production and initial characterization of transformed plants constitutively expressing proteinase inhibitors (12 months); analysis of effects of cellular redox state on proteinase activity and chloroplast protein turnover (24 months); analysis of redox signalling cascades regulating chloroplast protein turnover (36 months).