Salinity stress proteins

Ramagopal, S. (1987). Salinity stress induced tissue-specific proteins in barley seedlings. Plant Physiology, 84, 324-31. 

Li, J., Steen, H., and Gygi, S.P. (2003) Protein profiling with cleavable isotope-coded affinity tag (cICAT) reagents. The yeast salinity stress response. Mol. Cell. Proteomics 2, 1198-1204. 

Shepard JL, Olsson B, Tedengren M, Bradley BP. Protein expression signatures identified in Mytilus edulis exposed to PCBs, copper and salinity stress. Mar Environ Res 2000 50(l-5) 337-40. 

Brassinosteroids (BSs) represent a new group of plant hormones that possess a broad spectrum of physiological activities (1,2). A most Intriguing property of BSs Is their capacity to Increase stress resistance In plants, but the mechanism of such an antistress activity still remains unknown (1). As cell stress resistance Is usually associated with stress protein synthesis (3 4) our aim was to study the BS effect on protein synthesis and ultrastructure of wheat leaf cells at normal temperature and under heat shock conditions. We have also studied the Influence of BSs on mesophyll cell ultrastructure under saline stress. 

BSs protected cereal leaf cells from heat shock or saline stress. Leaf pre treatment with BSs decreased cell ultrastructure degradation from heat shock and high salt conditions. BSs increased HSG formation which is supposed to protect preformed mRNA in plant cells during heating. BSs enhanced heat shook resistance of the leaf protein-synthesizing system. The effect of BSs on RNA and protein synthesis was shown earlier (14). We observed protein synthesis activation in wheat leaves by BSs in normal and under stress conditions. Two-dimensional SDS-FAAGE of dS-methionine labeled proteins demonstrated BS-induced changes in the set of polypeptides synthesized in leaves and in the rate of their synthesis. 

Proteomics in parasitic flatworms can be completed on intracellular fractions (e.g. microsomal or cytosol) or at the host-interface on excretory-secretory (ES) products. ES analysis can be completed during in vitro culture or in vivo by, for example, bile or gut content analysis. In all cases, a rapid and careful preparation is vital to prevent altered pro-teomic profiles due to stress responses (upreg-ulation of heat shock proteins) and action of proteases. Parasitic flatworms are best extracted from fresh host material, washed with a buffered saline solution at approximately the host s body temperature. In F. hepatica, for example, this will allow regurgitation of gut contents to remove digested material from, and removal of host material adherent to the outer surfaces of the parasite (Jefferies et al., 2001), both of which can subsequently complicate separation and identification. 

Baer, K.N. and P. Thomas. Influence of capture stress, salinity and reproductive status on zinc, proteins in the liver of three marine teleost species. Mar. Environ. Res. 28 277-287, 1990. 

Although osmo-conformation allows the clam to survive in highly saline environments, the processes of protein synthesis and repair are energy-intensive, and are estimated to cost 20%-25% of total energy expenditure under nonstressful conditions. The energy used to accumulate amino acids in response to environmental elevated salinities is not available for other survival and reproductive purposes, and probably makes the clam susceptible to succumb to other stresses. 

Heat shock proteins are not unique to high-temperature stress some are induced by other environmental stresses such as water deficit, chemical exposure, wounding, low temperature, and salinity (Taiz and Zeiger, 1998). Exposure to one type of stress can cause protection against exposure to others. Therefore, production and isolation of heat shock proteins in bioreactors has commercial value when they are subsequently applied to stressed organisms. 

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