Salt stress negatively affects plant growth and crop productivity. As an ideal model pathway of salt tolerance in glycophyte. To better understand the molecular mechanisms of salt-response in glycophyte, 466 of 15,768 Arabidopsis thaliana proteins with the GO term of biological with known genetic background, Arabidopsis thaliana has been widely applied to disclose the process 'response to salt stress' were retrieved from UniPort and analyzed by bioinformatics tools of PANTHER, DAVID, KEGG, Cytoscape and STRING. Our results not only indicated the involvement of salt-responsive proteins in various pathways and interaction networks, but also demonstrated the more complicated cross-tolerances to both abiotic stresses (osmosis, water deprivation, abscisic acid, cold, heat, light and wounding) and biotic stresses (bacterium and fungus) and multiple subcellular locations of these salt-responsive proteins. Furthermore, protein activities of superoxide dismutase (SOD) and peroxidase (POD) in Arabidopsis thaliana were determined under salt, cold and osmotic stresses, which validated the hypothesis of cross-tolerance to multiple stresses. Our work will greatly improve the current knowledge of salt tolerance mechanism in glycophytes and provide potential salt-responsive candidates for promoting plant growth and increasing crop output.

Endogenous peptides that represent biological and pathological information of disease have attracted interest for diagnosis. However, the extraction of those low abundance peptides is still a challenge because of the complexity of human bodily fluids (HBF). Hepcidin, a peptide hormone, has been recognized as a biomarker for iron-related diseases. There is no rapid and reliable way to enrich them from HBF. Here we describe a peptides extraction approach based on nanoporous silica thin films to successfully detect hepcidin from HBF. Cooperative functions of nanopore to biomolecule, including capillary adsorption, size-exclusion and electrostatic interaction, were systematically investigated to immobilize the target peptide. To promote this new approach to clinical practices, we further applied it to successfully assay the hepcidin levels in HBF provided by healthy volunteers and patients suffering from inflammation. Our finding provides a high-throughput, rapid, label-free and cost-effective detection method for capturing and quantifying low abundance peptides from HBF.

Salt is one of the major abiotic stresses limiting the productivity and the geographical distribution of crops. To gain a better understanding of NaCl stress responses in model plant Arabidopsis roots, the protein changes in the abundance (Coomassie Brilliant Blue R-350 stain) and phosphorylation (Pro-Q Diamond stain) were examined using twodimensional electrophoresis coupled with mass spectrometry (MS). Seventeen unique proteins differentially changed in abundance, phosphorylation, or both in response to NaCl. Nonsynchronous differences were found between total proteins and phosphorylated proteins. Protein synthesis, proteolysis, post-translational modifications, and isoforms might cause the differential protein redundancies. The identified proteins are involved in binding, catalysis, signal transduction, transport, metabolisms of cell wall and energy, and reactive oxygen species (ROS) scavenging and defense. These protein changes provide new avenues of investigation into the underlying salt stress response in Arabidopsis roots and demonstrate the advantages of proteomic approach in plant biology studies.

Two-dimensional electrophoresis (2-DE) showed the variation expression of Arabidopsis thaliana root proteins between wild type and its salt-tolerant mutant obtained from cobalt-60 g ray radiation. Forty-six differential root protein spots were reproducibly presented on 2-DE maps, and 29 spots were identified by matrix assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MS). Fifteen protein spots corresponding to 10 proteins, and 14 protein spots corresponding to 9 proteins were constitutively up-regulated and downregulated in the salt-tolerant mutant root. Bioinformatic analysis indicated that those differential proteins might be involved in the regulation of redox homeostasis, nucleotide metabolism, signal transduction, stress response and defense, carbohydrate metabolism, and cell wall metabolism. Peroxidase 22 might be a versatile enzyme and might play dual roles in both cell wall metabolism and regulation of redox homeostasis. Our work provides not only new insights into salt-responsive proteins in root, but also the potential salt-tolerant targets for further dissection of molecular mechanism adapted by plants during salt stress.

Salt stress is a major abiotic stress limiting the productivity and the geographical distribution of many plant species. Arabidopsis thaliana is an excellent model with rich genetic resources for modern plant biology research. To comprehensively and representatively understand salt-response mechanisms in A. thaliana, we applied the first attempt to use the most data (252 of 10,469 reviewed A. thaliana protein) from public protein database for displaying the enriched protein domains, Kyoto Encyclopedia of Genes and Genomes pathways, molecular functions, and cell localizations involved in salt-response. The data were analyzed by Database for Annotation Visualization and Integrated Discovery. Our results indicated salt-response proteins cross-talked not only with drought and temperature stress as previously reported but also with further stresses such as bacterium, light, metal ion, radiation, and wounding stress. Multiple cellular localizations under salt stress indicated proteins were versatile. In addition, 27 proteins have the characteristics with response to multiple stresses and localization in multiple places. We called it the 'space-stress' double cross-talk effects, which indicated that A. thaliana proteins dealt with salt stress and other stresses in a reciprocal economical way. An enriched bioinformatics analysis of the large data could provide clues and basis for the development of salt-response potential biomarkers for plant growth and crop productivity.