Multivariate analysis of protein profiles of metal hyperaccumulatorThlaspi caerulescens accessions

Abstract

Thlaspi caerulescens is increasingly acknowledged as one of the best models for studying metal hyperaccumulation in plants. In order to study the mechanisms underlying metal hyperaccumulation, we used proteomic profiling to identify differences in protein intensities among three T. caerulescens accessions with pronounced differences in tolerance, uptake and root to shoot translocation of Zn and Cd. Proteins were separated using two-dimensional electrophoresis and stained with SYPRO Orange. Intensity values and quality scores were obtained for each spot by using PDQuest software. Principal component analysis was used to test the separation of the protein profiles of the three plant accessions at various metal exposures, and to detect groups of proteins responsible for the differences. Spot sets representing individual proteins were analysed with the analysis of variance and non-parametric Kruskal-Wallis test. Clearest differences were seen among the Thlaspi accessions, while the effects of metal exposures were less pronounced. The 48 tentatively identified spots represent core metabolic functions (e.g. photosynthesis, nitrogen assimilation, carbohydrate metabolism) as well as putative signalling and regulatory functions. The possible roles of some of the proteins in heavy metal accumulation and tolerance are discussed.

Differential Proteome Analysis of <i>Chlamydomonas reinhardtii</i> Response to Arsenic Exposure

“…Degradation of RuBisCO in metal non-tolerant plants has been reported in response to redox-reaction associated heavy metals such as copper and cadmium and other metals including mercury, cobalt, manganese and zinc [43][44][45]. A down-regulation of RuBisCO subunits, on the other hand, was observed in hyperaccumulator plants following exposure to metal stress [46] and also was shown in a previous investigation using Asexposed Dwarf Sunflowers [12], suggesting a decrease in net photosynthesis under metal stress. The large subunit of RuBisCO was not detected because it was removed by the ammonium sulfate precipitation.…”

Characterization of the glyoxalase 1 gene TcGLX1 in the metal hyperaccumulator plant Thlaspi caerulescens

“…32 kDa and isoelectric points (pI) of 5.7 for LC and LE and 6.1 for LM. These values corresponded to those expected based on two-dimensional electrophoresis (2-DE) of the proteins isolated from the T. caerulescens accessions LC and LE (Tuomainen et al 2006(Tuomainen et al , 2010. The TcGLX1 sequences in the three accessions differed only in five amino acids (1.8 %).…”

Comparative analysis of proteomic changes in contrasting flax cultivars upon cadmium exposure

“…Glutamine synthetase is involved in GSH and, consequently, PCs biosynthesis, via glutamate biosynthesis. Glutamine synthetase has been found to be up-regulated in Cd-treated Arabidopsis cells and poplar [24,25], and is positively correlated with the Cd tolerance of three accessions of the hyperaccumulator Thlaspi caerulescens [36]. Furthermore, two enzymes involved in the methyl cycle, methionine synthetase (K21) and S-adenosyl-L-methionine synthetase (K18), were found to be up-regulated by Cd in both flax cultivars, Jitka and Tábor.…”