title: Suppression of Chloroplastic Alkenal/One Oxidoreductase Represses the Carbon Catabolic Pathway in Arabidopsis Leaves during Night.
abstract: Lipid-derived reactive carbonyl species (RCS) possess electrophilic moieties and cause oxidative stress by reacting with cellular components. Arabidopsis (Arabidopsis thaliana) has a chloroplast-localized alkenal/one oxidoreductase (AtAOR) for the detoxification of lipid-derived RCS, especially α,β-unsaturated carbonyls. In this study, we aimed to evaluate the physiological importance of AtAOR and analyzed AtAOR (aor) mutants, including a transfer DNA knockout, aor (T-DNA), and RNA interference knockdown, aor (RNAi), lines. We found that both aor mutants showed smaller plant sizes than wild-type plants when they were grown under day/night cycle conditions. To elucidate the cause of the aor mutant phenotype, we analyzed the photosynthetic rate and the respiration rate by gas-exchange analysis. Subsequently, we found that both wild-type and aor (RNAi) plants showed similar CO2 assimilation rates; however, the respiration rate was lower in aor (RNAi) than in wild-type plants. Furthermore, we revealed that phosphoenolpyruvate carboxylase activity decreased and starch degradation during the night was suppressed in aor (RNAi). In contrast, the phenotype of aor (RNAi) was rescued when aor (RNAi) plants were grown under constant light conditions. These results indicate that the smaller plant sizes observed in aor mutants grown under day/night cycle conditions were attributable to the decrease in carbon utilization during the night. Here, we propose that the detoxification of lipid-derived RCS by AtAOR in chloroplasts contributes to the protection of dark respiration and supports plant growth during the night.
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Daisuke
authors.identifier: 0000-0003-0880-5877
authors.initials: D
authors.lastname: Takagi
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ifuku
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Kanako Ikeda
authors.initials: KI
authors.lastname: Inoue
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Pyoyun
authors.initials: P
authors.lastname: Park
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tamoi
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Hironori
authors.initials: H
authors.lastname: Inoue
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Sakamoto
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.).
authors.forename: Ryota
authors.initials: R
authors.lastname: Saito
authors.affiliation: Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science (D.T., K.-i.I., K.I.I., P.P., H.I., K.S., R.S., C.M.), and Center for Support to Research and Education Activities (P.P.), Kobe University, Nada, Kobe 657-8501, Japan;Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan (K.I.); andFaculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan (M.T.) cmiyake@hawk.kobe-u.ac.jp.
authors.forename: Chikahiro
authors.identifier: 0000-0002-2426-2377
authors.initials: C
authors.lastname: Miyake
mesh_terms: D000171:Acrolein / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002244:Carbon / Q000378:metabolism*; D019069:Cell Respiration / Q000528:radiation effects; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000201:enzymology* / Q000528:radiation effects; D004269:DNA, Bacterial / Q000235:genetics; D003624:Darkness; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D008027:Light; D009154:Mutation / Q000235:genetics; D009584:Nitrogen / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism*; D050837:Oxidoreductases Acting on Aldehyde or Oxo Group Donors / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010788:Photosynthesis; D010936:Plant Extracts / Q000378:metabolism; D018515:Plant Leaves / Q000201:enzymology* / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013213:Starch / Q000378:metabolism; D013489:Suppression, Genetic
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D010936:Plant Extracts; C036483:T-DNA; D002734:Chlorophyll; D002244:Carbon; D000171:Acrolein; D013213:Starch; D010088:Oxidoreductases; C000618213:AOR protein, Arabidopsis; D050837:Oxidoreductases Acting on Aldehyde or Oxo Group Donors; D009584:Nitrogen