Disulfide Proteomics: Current Status in Thioredoxin Biochemistry and Industrial Research

Abstract

nisms of various human diseases and, more practically, to identify potential drug targets and biomarkers.In 2001, the concept of proteomics has been incorporated into Trx-linked studies. Yano et al. 57 and Motohashi et al. 37 independently developed major proteomic approaches based on discrete principles. The affinity column strategy 37 allows the concentration of the targets, while the fluorescent gel approach 57 is applicable to both in vitro and in vivo analyses. These two methods, with their improved versions, have since been applied to elucidate Trx-linked biochemistry 26 , and the number of putative targets has reached 400 35 . Following a brief introduction of these two basic methods, the present short review focuses on the recent advancement of a technique that can effectively tackle problems such as target authenticity. The review also introduces two industrial research areas, food processing and medical investigation, in which proteomic studies are underway. Proteomic approaches to identify Trx targetsIn this section, basic proteomic methods are briefly introduced, while application of the techniques to plant IntroductionPost-translational modification (PTM) functions in a broad spectrum of biology. Among the regulatory mechanisms involved, reversible protein phosphorylation has been most widely studied and developing the phosphoproteomics technique has enhanced our understanding of this mode of regulation. Meanwhile, a growing body of evidence suggests that reversible reduction/oxidation (redox) of protein disulfide bonds regulates critical processes in all cell types 12 . Thioredoxins (Trxs) are small (10-14 kDa), widely distributed redox proteins involved in the regulation of numerous target proteins via thiol/disulfide exchanges, and thus play key roles in maintaining cellular redox homeostasis 34,44 . Thus, a better understanding of redox biology could be achieved if more were known about their target proteins. Moreover, the knowledge obtained will be useful in developing new variety of plants/crops with improved yield, disease-resistance and cultivation suitability which should benefit developing countries. In medical studies, this knowledge may also reveal important clues to understand the mecha-JARQ 46 (4), 277 -285 (2012) AbstractRedox regulation is a central control element across a broad spectrum of biology. Thioredoxin (Trx), a widely distributed disulfide enzyme, participates in the control of numerous target proteins, thus playing a key role in regulatory processes. Identification of Trx's targets will therefore aid the elucidation of redox biology. Two recently developed procedures, one based on thiol-specific probes and the other on affinity trapping, have facilitated the labeling or isolation of potential Trx targets that were later identified with proteomic approaches. Accordingly, the number of identified targets in plants has increased to 400. This review describes recent advances in proteomic strategies that are effectively overcoming challenging problems such as the evaluation ...

Further Studies on the Protein Chemistry and Property of Glutathione-Added Rice Bread : Evidence of Glutathionylation of Batter Protein as well as Crumb Structure/Sensory Evaluation

“…This unproven theory hypothesizes that water absorption by the starch molecule is interfered with by a network comprising disulfide-linked proteins attached to the starch granule 4 . The main component of the barrier is supposed to be glutelin polymers, while other low molecular proteins such as albumins, globulins and prolamins are entrapped in the large *Corresponding author: e-mail hyano@affrc.go.jp Received 27 September 2012; accepted 8 February 2013. macromolecular complexes 6 .…”