PARENT SESSION
Posters P6B Photosynthetic acclimation: Mechanisms and gene expression. Abstracts (531-578)

Chloroplast redox sensors and response regulators. Sujith Puthiyaveetil^*,1, Jens Forsberg², Jörgen Strom¹, John Allen¹, ¹ Plant Biochemistry, Lund, Sweden² Medical Biochemistry and Microbiology, Uppsala, Sweden

ABSTRACT- The nature of bacterial descent of eukaryotic energy converting organelles, chloroplasts and mitochondria, the prevalence of redox signalling two component proteins in prokaryotes, and the recent finding of two-component proteins in eukaryotic genomes, all support the notion of two component proteins as the signalling units for the observed redox responsive organellar gene expression. Arabidopsis and Pea thylakoids show distinct immunoreactive bands when searched with antibodies raised against a conserved motif in sensor histidine kinases. These candidate proteins are immunoprecipitated and sent for identification by mass spectroscopy. Genome information of Arabidopsis is used to predict plastid targeted sensor histidine kinases and response regulators. We have identified a number of candidate proteins. A knock-out Arabidopsis line for a predicted sensor histidine kinase is screened in different ways for an aberrant redox signalling phenotype.

KEY WORDS: Redox signalling, Knock-out histidine kinase mutant, Two component proteins, Chloroplasts