Dataset Information

Analysis of Copper-Binding Proteins in Rice Radicles Exposed to Excess Copper and Hydrogen Peroxide Stress.

ABSTRACT: Copper (Cu) is an essential micronutrient for plants, but excess Cu can inactivate and disturb the protein function due to unavoidable binding to proteins at the cellular level. As a redox-active metal, Cu toxicity is mediated by the formation of reactive oxygen species (ROS). Cu-binding structural motifs may alleviate Cu-induced damage by decreasing free Cu(2+) activity in cytoplasm or scavenging ROS. The identification of Cu-binding proteins involved in the response of plants to Cu or ROS toxicity may increase our understanding the mechanisms of metal toxicity and tolerance in plants. This study investigated change of Cu-binding proteins in radicles of germinating rice seeds under excess Cu and oxidative stress using immobilized Cu(2+) affinity chromatography, two-dimensional electrophoresis, and mass spectra analysis. Quantitative image analysis revealed that 26 protein spots showed more than a 1.5-fold difference in abundances under Cu or H2O2 treatment compared to the control. The identified Cu-binding proteins were involved in anti-oxidative defense, stress response and detoxification, protein synthesis, protein modification, and metabolism regulation. The present results revealed that 17 out of 24 identified Cu-binding proteins have a similar response to low concentration Cu (20 ?M Cu) and H2O2 stress, and 5 out of 24 were increased under low and high concentration Cu (100 ?M Cu) but unaffected under H2O2 stress, which hint Cu ions can regulate Cu-binding proteins accumulation by H2O2 or no H2O2 pathway to cope with excess Cu in cell. The change pattern of these Cu-binding proteins and their function analysis warrant to further study the roles of Cu ions in these Cu-binding proteins of plant cells.

SUBMITTER: Zhang H

PROVIDER: S-EPMC4987373 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Analysis of Copper-Binding Proteins in Rice Radicles Exposed to Excess Copper and Hydrogen Peroxide Stress.

Zhang Hongxiao H Xia Yan Y Chen Chen C Zhuang Kai K Song Yufeng Y Shen Zhenguo Z

Frontiers in plant science 20160817

Copper (Cu) is an essential micronutrient for plants, but excess Cu can inactivate and disturb the protein function due to unavoidable binding to proteins at the cellular level. As a redox-active metal, Cu toxicity is mediated by the formation of reactive oxygen species (ROS). Cu-binding structural motifs may alleviate Cu-induced damage by decreasing free Cu(2+) activity in cytoplasm or scavenging ROS. The identification of Cu-binding proteins involved in the response of plants to Cu or ROS toxi ...[more]

PMID: 27582750

Similar Datasets

Project description:To better understand the mechanisms involved in the heavy metal stress response and tolerance in plants, a proteomic approach was used to investigate the differences in Cu-binding protein expression in Cu-tolerant and Cu-sensitive rice varieties. Cu-binding proteins from Cu-treated rice roots were separated using a new IMAC method in which an IDA-sepharose column was applied prior to the Cu-IMAC column to remove metal ions from protein samples. More than 300 protein spots were reproducibly detected in the 2D gel. Thirty-five protein spots exhibited changes greater than 1.5-fold in intensity compared to the control. Twenty-four proteins contained one or more of nine putative metal-binding motifs reported by Smith et al., and 19 proteins (spots) contained one to three of the top six motifs reported by Kung et al. The intensities of seven protein spots were increased in the Cu-tolerant variety B1139 compared to the Cu-sensitive variety B1195 (p<0.05) and six protein spots were markedly up-regulated in B1139, but not detectable in B1195. Four protein spots were significantly up-regulated in B1139, but unchanged in B1195 under Cu stress. In contrast, two protein spots were significantly down-regulated in B1195, but unchanged in B1139. These Cu-responsive proteins included those involved in antioxidant defense and detoxification (spots 5, 16, 21, 22, 28, 29 and 33), pathogenesis (spots 5, 16, 21, 22, 28, 29 and 33), regulation of gene transcription (spots 8 and 34), amino acid synthesis (spots 8 and 34), protein synthesis, modification, transport and degradation (spots 1, 2, 4, 10, 15, 19, 30, 31, 32 and 35), cell wall synthesis (spot 14), molecular signaling (spot 3), and salt stress (spots 7, 9 and 27); together with other proteins, such as a putative glyoxylate induced protein, proteins containing dimeric alpha-beta barrel domains, and adenosine kinase-like proteins. Our results suggest that these proteins, together with related physiological processes, play an important role in the detoxification of excess Cu and in maintaining cellular homeostasis.

Project description:Hydrogen peroxide (H2O2) plays a dual role in plants as the toxic by-product of normal cell metabolism and as a regulatory molecule in stress perception and signal transduction. However, a clear inventory as to how this dual function is regulated in plants is far from complete. In particular, how plants maintain survival under oxidative stress via adjustments of the intercellular metabolic network and antioxidative system is largely unknown. To investigate the responses of rice seedlings to H2O2 stress, changes in protein expression were analyzed using a comparative proteomics approach. Treatments with different concentrations of H2O2 for 6 h on 12-day-old rice seedlings resulted in several stressful phenotypes such as rolling leaves, decreased photosynthetic and photorespiratory rates, and elevated H2O2 accumulation. Analysis of approximately 2000 protein spots on each two-dimensional electrophoresis gel revealed 144 differentially expressed proteins. Of them, 65 protein spots were up-regulated, and 79 were down-regulated under at least one of the H2O2 treatment concentrations. Furthermore 129 differentially expressed protein spots were identified by mass spectrometry to match 89 diverse protein species. These identified proteins are involved in different cellular responses and metabolic processes with obvious functional tendencies toward cell defense, redox homeostasis, signal transduction, protein synthesis and degradation, photosynthesis and photorespiration, and carbohydrate/energy metabolism, indicating a good correlation between oxidative stress-responsive proteins and leaf physiological changes. The abundance changes of these proteins, together with their putative functions and participation in physiological reactions, produce an oxidative stress-responsive network at the protein level in H2O2-treated rice seedling leaves. Such a protein network allows us to further understand the possible management strategy of cellular activities occurring in the H2O2-treated rice seedling leaves and provides new insights into oxidative stress responses in plants.

Project description:BackgroundPlant apoplast is the prime site for signal perception and defense response, and of great importance in responding to environmental stresses. Hydrogen peroxide (H(2)O(2)) plays a pivotal role in determining the responsiveness of cells to stress. However, how the apoplast proteome changes under oxidative condition is largely unknown. In this study, we initiated a comparative proteomic analysis to explore H(2)O(2)-responsive proteins in the apoplast of rice seedling roots.Methodology/principal findings14-day-old rice seedlings were treated with low concentrations (300 and 600 µM) of H(2)O(2) for 6 h and the levels of relative electrolyte leakage, malondialdehyde and H(2)O(2) were assayed in roots. The modified vacuum infiltration method was used to extract apoplast proteins of rice seedling roots, and then two-dimensional electrophoresis gel analysis revealed 58 differentially expressed protein spots under low H(2)O(2) conditions. Of these, 54 were successfully identified by PMF or MS/MS as matches to 35 different proteins including known and novel H(2)O(2)-responsive proteins. Almost all of these identities (98%) were indeed apoplast proteins confirmed either by previous experiments or through publicly available prediction programs. These proteins identified are involved in a variety of processes, including redox homeostasis, cell wall modification, signal transduction, cell defense and carbohydrate metabolism, indicating a complex regulative network in the apoplast of seedling roots under H(2)O(2) stress.Conclusions/significanceThe present study is the first apoplast proteome investigation of plant seedlings in response to H(2)O(2) and may be of paramount importance for the understanding of the plant network to environmental stresses. Based on the abundant changes in these proteins, together with their putative functions, we proposed a possible protein network that provides new insights into oxidative stress response in the rice root apoplast and clues for the further functional research of target proteins associated with H(2)O(2) response.

Dataset Information

Analysis of Copper-Binding Proteins in Rice Radicles Exposed to Excess Copper and Hydrogen Peroxide Stress.

Publications

Analysis of Copper-Binding Proteins in Rice Radicles Exposed to Excess Copper and Hydrogen Peroxide Stress.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure