In comparison with Arabidopsis thaliana wild type plants, onset of leaf death (old)
mutants show advanced leaf senescence. The aim of this work was to investigate the molecular processes of early leaf senescence by relative quantitative proteomics.
Two-dimensional difference gel electrophoresis (DIGE) was employed to determine differences in protein concentration in A. thaliana with normal and altered leaf senescence. The identity of regulated proteins was determined by mass spectrometry
(MS). Differences in subunits of ribulose 1,5-bisphosphate carboxylase/oxygenase and several members of glutathione S-transferase phi-class were found.
A further approach was developed to assess for the first time the applicability of metabolic 15N-labeling combined with MS to relative quantitative proteomic analysis of A. thaliana. The
two quantification methods, DIGE and 15N-labeling combined with MS for the accurate determination of protein concentration ratios, showed a good correlation.