title: Disulfide proteome yields a detailed understanding of redox regulations: a model study of thioredoxin-linked reactions in seed germination.
abstract: Accumulating evidence suggests that redox regulations play important roles in a broad spectrum of biological processes. Recently, Yano et al. developed a disulfide proteome technique that comprehensively visualizes redox change in proteins. In this paper, using the disulfide proteome, we examined rice bran and identified fragments of embryo-specific protein and dienelactone hydrolase as putative targets of thioredoxin. Also, monitoring of the endogenous and recombinant effects of thioredoxin on rice bran proteins and supporting in vivo observations propose a mechanism of redox regulation in seed germination, in which thioredoxin activates cysteine protease with a concurrent unfolding of its substrate, the embryo-specific protein. Our findings suggest that thioredoxin controls the lifetime of specific proteins effectively by regulating the redox reactions coordinately. The model study demonstrates that the disulfide proteome technique is useful not only for identifying targets of thioredoxin, but also for clarify the detailed mechanism of redox regulation.
authors.affiliation: Department of Rice Research, National Institute of Crop Science, Kannondai, Tsukuba 305-8518, Japan. hyano@affrc.go.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yano
authors.forename: Masaharu
authors.initials: M
authors.lastname: Kuroda
mesh_terms: D000595:Amino Acid Sequence; D003546:Cysteine Endopeptidases / Q000378:metabolism; D004220:Disulfides / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D018525:Germination; D006868:Hydrolysis; D007525:Isoelectric Focusing; D008969:Molecular Sequence Data; D012275:Oryza / Q000196:embryology; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000737:chemistry*; D020543:Proteome; D012639:Seeds / Q000502:physiology*; D013879:Thioredoxins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004220:Disulfides; D010940:Plant Proteins; D020543:Proteome; D013879:Thioredoxins; D003546:Cysteine Endopeptidases