thioredoxins (trxs) are small heat-stable proteins that are involved in the cell redox regulation and are present in all organisms from prokaryotes to higher eukaryotes. in higher plants, trxs can be classified into six different groups namely: the chloroplastic trxs f, m, x, and y, the mitochondrial trx o and the trxs h. the trxs h are represented by a small multigenic family that participate ...

We tested the hypothesis that oxidant-injured cells upregulate thioredoxin, whereas oxidant-stressed, but not injured, cells upregulate interleukin (IL)-8 after injury. We exposed primary human tracheobronchial epithelial cells and transformed human bronchial epithelial cells (BEAS-2B S.6) to 0, 200, 400, or 600 microM H(2)O(2) for 1 h followed by an additional 7 h of incubation. Subsequently, ...

Thioredoxins h are ubiquitous proteins reduced by NADPH- thioredoxin reductase (NTR). They are able to reduce disulphides in target proteins. In monocots, thioredoxins h accumulate at high level in seeds and show a predominant localization in the nucleus of seed cells. These results suggest that the NTR-thioredoxin h system probably plays an important role in seed physiology. To date, the study...

Thioredoxins are small proteins of approximately 12 kD that reduce disulfide bridges of target proteins by the reversible formation of a disulfide bridge between two neighboring Cys residues present in the active site (Try-Cys-Gly-Pro-Cys). Thioredoxins have been found to regulate a variety of biological reactions in prokaryotic and eukaryotic cells (Holmgren, 1985). In higher plants, two thior...

The extensive use of heavy metals and nanoparticles (NPs) has led to their release into the environment that might have negative impacts on both organisms and the environment. In this study, the molecular responses of wheat seedlings to silver nitrate and silver nanoparticles (AgNPs) were assessed by transcript accumulation analysis of genes coding for products potentially involved in heavy met...

The tumor suppressor PTEN regulates cell migration, growth, and survival by removing the 3'-phosphate of phosphoinositides. Exposure of purified PTEN or of cells to H(2)O(2) resulted in inactivation of PTEN in a time- and H(2)O(2) concentration-dependent manner. Analysis of various cysteine mutants, including mass spectrometry of tryptic peptides, indicated that the essential Cys(124) residue i...

the thioredoxin system, comprising thioredoxin (trx), thioredoxin reductase (trxr) and nadph, is one of the major cellular antioxidant systems, implicated in a large and growing number of biological functions. trx acts as an oxidoreductase via a highly conserved dithiol/disulfide motif located in the active site ( trp-cys-gly-pro- cys-lys-). different factors are involved in the regulation of t...

The thioredoxin system is a key cellular antioxidant system and is highly expressed in cancer cells, especially in more aggressive and therapeutic resistant tumors. We analysed the expression of the thioredoxin system in the MDA-MB-231 breast cancer cell line under conditions mimicking the tumor oxygen microenvironment. We grew breast cancer cells in either prolonged hypoxia or hypoxia followed...

Evidence is reported for the presence of the mRNAs of thioredoxin h, oryzacystatin-I, and actin in the rice phloem sap collected by the insect laser method. As the sieve element, the core component of the phloem, is enucleated, these macromolecules are probably transported from the companion cells.