OsMSRA4.1 and OsMSRB1.1, two rice plastidial methionine sulfoxide reductases, are involved in abiotic stress responses.
In proteins, methionine residues are especially sensitive to oxidation, leading to the formation of S- and R-methionine sulfoxide diastereoisomers, and these two methionine sulfoxides can be specifically reversed by two types of methionine sulfoxide reductases (MSRs), MSRA and MSRB. Previously, we have identified a gene encoding a putative MSR from NaCl-treated roots of Brazilian upland rice (Oryza sativa L. cv. IAPAR 9) via subtractive suppression hybridization (Wu et al. in Plant Sci 168:847-853, 2005). Blast database analysis indicated that at least four MSRA and three MSRB orthologs exist in rice, and two of them, OsMSRA4.1 and OsMSRB1.1, were selected for further functional analysis. Expression analysis showed that both OsMSRA4.1 and OsMSRB1.1 are constitutively expressed in all organs and can be induced by various stress conditions. Subcellular localization and in vitro activity assay revealed that both OsMSR proteins are targeted to the chloroplast and have MSR activity. Overexpression of either OsMSRA4.1 or OsMSRB1.1 in yeast enhanced cellular resistance to oxidative stress. In addition, OsMSRA4.1-overexpressing transgenic rice plants also showed enhanced viability under salt treatment. Our results provide genetic evidence of the involvement of OsMSRs in the plant stress responses.
State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences (CAS), 100101 Beijing, China.
Xiaoli
X
Guo
Yaorong
Y
Wu
Yiqin
Y
Wang
Yanmin
Y
Chen
Chengcai
C
Chu
D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002736:Chloroplasts / Q000201:enzymology; D003080:Cold Temperature; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006358:Hot Temperature; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D051150:Methionine Sulfoxide Reductases; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000201:enzymology* / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D018087:Plastids / Q000201:enzymology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D012965:Sodium Chloride / Q000494:pharmacology
D007527:Isoenzymes; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D012965:Sodium Chloride; D000040:Abscisic Acid; D010088:Oxidoreductases; D051150:Methionine Sulfoxide Reductases; C027219:methionine sulfoxide reductase