This book contains a broad survey on the peroxiredoxins. It involves almost all groups that contributed significant insights into the emerging field. Coverage discusses the diverse biological roles of the new protein family in the context of other antioxidant systems like those based on heme or selenium catalysis. In addition, the book highlights related future perspectives.

This book contains a broad survey on the peroxiredoxins. It involves almost all groups that contributed significant insights into the emerging field. Coverage discusses the diverse biological roles of the new protein family in the context of other antioxidant systems like those based on heme or selenium catalysis. In addition, the book highlights related future perspectives.

The peroxiredoxin family was discovered approximately 30 years ago and is now recognized as one of the most important families of enzymes related to antioxidant defense and cellular signaling. Peroxiredoxin 6 shares the basic enzymatic functions that characterize this family, but also exhibits several unique and crucial activities. These include the ability to reduce phospholipid hydroperoxides, phospholipase A2 activity, and an acyl transferase activity that is important in phospholipid remodeling. This book describes the available models for investigating the unique functions of PRDX6 and its role in normal physiological function, as well its roles in the pathophysiology of diseases including cancer, diseases of the eye, and male fertility.

When we worked on Down Syndrome brain in the past we have been focus ing on adult brain. This was a major step forwards as most work on Down Syndrome was carried out on fibroblasts or other tissues and, moreover, we introduced proteomics to identify and quantify brain protein expression. We considered evaluation of brain protein expression in Down Syndrome brain by and by more important than gene hunting at the nucleic acid level realiz ing the long unpredictable way from RNA to protein. The availability of fetal samples along with the proteomic appproach stimulated and reinforced studies on Down Syndrome brain. And indeed, it was found out that some observations on aberrant protein expression in adult Down Syndrome brain could not be verified in the fetal samples indi cating that neurodegeneration in adult Down Syndrome brain may have been responsible rather than trisomy 21. Using brains from the early second trimester of gestation led to the generation of a series of clues for the under standing of aberrant wiring of the brain in Down Syndrome and enabled the determination of altered key functions in early life; e. g. undetectably low drebrin was observed in Down Syndrome cortex, an integral constituent and marker for dendritic spines, main effectors of cross-talk between neurons. In addition, evaluation of the nature of the neuronal deficits in terms of neuro transmission markers could be established as well as neuronal density in fetal Down Syndrome cortex.

This book provides an overview of antioxidants and antioxidant enzymes and their role in the mechanisms of signaling and cellular tolerance under stress in plant systems. Major reactive oxygen species (ROS)-scavenging/modulating enzymes include the superoxide dismutase (SOD) that dismutates O2 into H2O2, which is followed by the coordinated action of a set of enzymes including catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GPX) and peroxiredoxins (Prx) that remove H2O2. In addition to the ROS scavenging enzymes, a number of other enzymes are found in various subcellular compartments, which are involved in maintaining such redox homeostasis either by directly scavenging particular ROS and ROS-byproducts or by replenishing antioxidants. In that respect, these enzymes can be also considered antioxidants. Such enzymes include monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), alternative oxidases (AOXs), peroxidases (PODs) and glutathione S-transferases (GSTs). Some non-enzymatic antioxidants, such as ascorbic acid (vitamin C), carotenes (provitamin A), tocopherols (vitamin E), and glutathione (GSH), work in concert with antioxidant enzymes to sustain an intracellular steady-state level of ROS that promotes plant growth, development, cell cycles and hormone signaling, and reinforces the responses to abiotic and biotic environmental stressors. Offering a unique compilation of information on antioxidants and antioxidant enzymes, this is a valuable resource for advanced students and researchers working on plant biochemistry, physiology, biotechnology, and signaling in cell organelles, and those specializing in plant enzyme technology.

Biological processes are driven by complex systems of functionally interacting signaling molecules. Thus, understanding signaling molecules is essential to explain normal or pathological biological phenomena. A large body of clinical and experimental data has been accumulated over these years, albeit in fragmented state. Hence, systems biological approaches concomitant with the understanding of each molecule are ideal to delineate signaling networks/pathways involved in the biologically important processes. The control of these signaling pathways will enrich our healthier life. Currently, there are more than 30,000 genes in human genome. However, not all the proteins encoded by these genes work equally in order to maintain homeostasis. Understanding the important signaling molecules as completely as possible will significantly improve our research-based teaching and scientific capabilities. This encyclopedia presents 350 biologically important signaling molecules and the content is built on the core concepts of their functions along with early findings written by some of the world’s foremost experts. The molecules are described by recognized leaders in each molecule. The interactions of these single molecules in signal transduction networks will also be explored. This encyclopedia marks a new era in overview of current cellular signaling molecules for the specialist and the interested non-specialist alike During past years, there were multiple databases to gather this information briefly and very partially. Amidst the excitement of these findings, one of the great scientific tasks of the coming century is to bring all the useful information into a place. Such an approach is arduous but at the end will infuse the lacunas and considerably be a streamline in the understanding of vibrant signaling networks. Based on this easy-approach, we can build up more complicated biological systems.

This Special Issue features recent data concerning thioredoxins and glutaredoxins from various biological systems, including bacteria, mammals, and plants. Four of the sixteen articles are review papers that deal with the regulation of development of the effect of hydrogen peroxide and the interactions between oxidants and reductants, the description of methionine sulfoxide reductases, detoxification enzymes that require thioredoxin or glutaredoxin, and the response of plants to cold stress, respectively. This is followed by eleven research articles that focus on a reductant of thioredoxin in bacteria, a thioredoxin reductase, and a variety of plant and bacterial thioredoxins, including the m, f, o, and h isoforms and their targets. Various parameters are studied, including genetic, structural, and physiological properties of these systems. The redox regulation of monodehydroascorbate reductase, aminolevulinic acid dehydratase, and cytosolic isocitrate dehydrogenase could have very important consequences in plant metabolism. Also, the properties of the mitochondrial o-type thioredoxins and their unexpected capacity to bind iron–sulfur center (ISC) structures open new developments concerning the redox mitochondrial function and possibly ISC assembly in mitochondria. The final paper discusses interesting biotechnological applications of thioredoxin for breadmaking.