RRC ID 12611
Author Onda Y, Nagamine A, Sakurai M, Kumamaru T, Ogawa M, Kawagoe Y.
Title Distinct roles of protein disulfide isomerase and P5 sulfhydryl oxidoreductases in multiple pathways for oxidation of structurally diverse storage proteins in rice.
Journal Plant Cell
Abstract In the rice (Oryza sativa) endosperm, storage proteins are synthesized on the rough endoplasmic reticulum (ER), in which prolamins are sorted to protein bodies (PBs) called type-I PB (PB-I). Protein disulfide isomerase (PDI) family oxidoreductase PDIL2;3, an ortholog of human P5, contains a conserved structural disulfide in the redox-inactive thioredoxin-like (TRX) domain and was efficiently targeted to the surface of PB-I in a redox active site-dependent manner, whereas PDIL1;1, an ortholog of human PDI, was localized in the ER lumen. Complementation analyses using PDIL1;1 knockout esp2 mutant indicated that the a and a' TRX domains of PDIL1;1 exhibited similar redox activities and that PDIL2;3 was unable to perform the PDIL1;1 functions. PDIL2;3 knockdown inhibited the accumulation of Cys-rich 10-kD prolamin (crP10) in the core of PB-I. Conversely, crP10 knockdown dispersed PDIL2;3 into the ER lumen. Glutathione S-transferase-PDIL2;3 formed a stable tetramer when it was expressed in Escherichia coli, and the recombinant PDIL2;3 tetramer facilitated α-globulin(C79F) mutant protein to form nonnative intermolecular disulfide bonds in vitro. These results indicate that PDIL2;3 and PDIL1;1 are not functionally redundant in sulfhydryl oxidations of structurally diverse storage proteins and play distinct roles in PB development. We discuss PDIL2;3-dependent and PDIL2;3-independent oxidation pathways that sustain disulfide bonds of crP10 in PB-I.
Volume 23(1)
Pages 210-23
Published 2011-1
DOI 10.1105/tpc.110.079509
PII tpc.110.079509
PMID 21278127
PMC PMC3051231
MeSH Endoplasmic Reticulum / metabolism Endosperm / metabolism Gene Knockdown Techniques Gene Knockout Techniques Genetic Complementation Test Mutation Oryza / enzymology* Oryza / genetics Oxidation-Reduction Oxidoreductases / metabolism* Protein Disulfide-Isomerases / metabolism* Protein Folding Seed Storage Proteins / metabolism*
IF 8.631
Times Cited 35
Rice Induced Mutation Lines