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Cold represents one of the major abiotic factors influencing plant growth and development worldwide. We analysed the long-term responsiveness of an Iranian spring wheat (cv. Kohdasht) to cold from a proteomic point of view, in order to unravel the molecular mechanisms helping a cold-sensitive cultivar to survive exposure to suboptimal temperatures. Plants were grown at 20 or 4°C until entering the reproductive stage and a cross-comparison on the leaf proteomes was performed. Quantitative analyses on protein alterations occurring upon low-temperature exposure showed a reinforcement in ascorbate recycling (dehydroascorbate reductase, ascorbate peroxidase) and protein processing (proteasome subunit, cysteine proteinase), as well as the accumulation of the enzyme devoted to tetrapyrrole resynthesis (glutamate semialdehyde aminomutase). In contrast, among proteins down-regulated after cold stress, we could identify some key Krebs cycle enzymes (isocitrate dehydrogenase, malate dehydrogenase), together with many photosynthesis-related proteins (oxygen-evolving complex proteins, ATP synthase subunits, ferredoxin NADPH oxidoreductase and some Calvin cycle enzymes). Physiological and biochemical parameters (such as shoot apex dissection, chlorophyll, proline and sugar content determination) sustained proteomics findings allowing the present research to contribute to the current knowledge on these long-term responses, which may be crucial to stress adaptation under field conditions., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The present study was aimed at revealing new insights into the analysis of storage-related processes occurring in the supernatants of platelet concentrates (PCs) derived from pooled buffy coats suspended in whole plasma. To reduce the dynamic range of plasma protein concentrations and access low-abundance proteins, we made use of a solid-phase combinatorial peptide ligand library, known under the trade name of ProteoMiner™. Afterwards, two-dimensional electrophoresis (2-DE) was coupled with mass spectrometry (MS) to reveal changes in proteomic profiles. Several storage-induced protein alterations were identified including changes to major plasma proteins. In particular, a precursor of the secretory form of clusterin was shown to accumulate during storage of PC supernatants, together with platelet-derived tropomyosin, suggesting a progressive loss of platelet integrity. Platelet-released proteins following activation have also been detected (alpha-1-B-glycoprotein, kininogen-1, and serpin proteinase inhibitor 8). Moreover, specific protein fragments (vitronectin, plakoglobin, hornerin, and apolipoprotein A-IV) were found to be modulated upon storage, possibly indicating a time-dependent buffy-coat PC deterioration. Globally, our findings provided the disclosure of unique proteins in PC supernatants with respect to previous studies conducted in similar experimental conditions, suggesting ProteoMiner enrichment technology to be a possible complementary tool in the identification of diagnostically relevant proteins as age/quality biomarkers of therapeutic products.

Consumer complaints against the blandness of modern lean meat and the frequent reference to the more strongly flavored meat that was available years ago have prompted reconsideration of high fat-depositing typical pig breeds. Casertana and Large White pig breeds are characterized by a different tendency toward fat accumulation as they exhibit opposite genetic and physiological traits with respect to the energy metabolism. These physiological differences were investigated in longissimus lumborum muscles through proteomics (2-DE, MS/MS) and microarray approaches. Data were analyzed for pathway and network analyses, as well as GO term enrichment of biological functions. As a result, Casertana showed a greater amount of proteins involved in glycolitic metabolism and mainly rely on fast-mobilizable energy sources. Large White overexpressed cell cycle and skeletal muscle growth related genes. Metabolic behavior and other implications are discussed.

The most crucial function of plant cell is to respond against stress induced for self-defence. This defence is brought about by alteration in the pattern of gene expression: qualitative and quantitative changes in proteins are the result, leading to modulation of certain metabolic and defensive pathways. Abiotic stresses usually cause protein dysfunction. They have an ability to alter the levels of a number of proteins which may be soluble or structural in nature. Nowadays, in higher plants high-throughput protein identification has been made possible along with improved protein extraction, purification protocols and the development of genomic sequence databases for peptide mass matches. Thus, recent proteome analysis performed in the vegetal Kingdom has provided new dimensions to assess the changes in protein types and their expression levels under abiotic stress. As reported in this review, specific and novel proteins, protein-protein interactions and post-translational modifications have been identified, which play a role in signal transduction, anti-oxidative defence, anti-freezing, heat shock, metal binding etc. However, beside specific proteins production, plants respond to various stresses in a similar manner by producing heat shock proteins (HSPs), indicating a similarity in the plant's adaptive mechanisms; in plants, more than in animals, HSPs protect cells against many stresses. A relationship between ROS and HSP also seems to exist, corroborating the hypothesis that during the course of evolution, plants were able to achieve a high degree of control over ROS toxicity and are now using ROS as signalling molecules to induce HSPs.

Abstract: In this work, proteomics was used to study the influence of both optimal and low temperatures on growth and development in a vernalization-requiring winter wheat (Triticum aestivum L. cv Cheyenne) after prolonged times of treatment. For this purpose, plants were grown at optimal temperature (20°C) for 14days (zero point) after which half were transferred to conditioned chambers kept at 4°C for a period of 63days. Cold tolerance, as estimated from lethal temperatures (LT50), and phenological development, as measured by final leaf number (FLN) and shoot apex dissection, were determined. Proteomic analysis indicated a down-accumulation of several photosynthesis-related proteins and a concomitant increase in abundance of some Calvin cycle enzymes. A cold-induced accretion of soluble sugars and proline was observed as well. In parallel, an increase of proteolysis accomplished by an up-modulation of TCA cycle enzymes was also noticed, probably suggesting an efficient recycling of amino acids as energy source. Proteomic analysis of plants grown at optimal temperature allowed to specifically discriminate cold-induced proteins and highlight molecular processes driven by vernalization. Among identified proteins typically involved in vernalization responses and floral transition we observed a marked increase of wrab17, wcor18 and glycine-rich RNA-binding proteins. [Copyright &y& Elsevier]