In UV-B irradiated rice high levels of Mn limits chloroplasts injury triggered by oxidative stress

Research output: Contribution to journalArticle

Abstract

The molecular mechanism to control the oxidative burst exerted by Mn accumulation in rice (Oryza sativaL.) plants, grown in hydroponics containing 0.5, 2 and 8mgl(-1) Mn and irradiated with a total biological effective UV-B irradiation of 20.825kJm(-2), was investigated in the chloroplasts at the 15th and 21st days after germination. In both experimental periods, Mn accumulation kinetics in the leaves and in the chloroplast lamellae displayed overall increases. Coupled to higher membrane selectivity, superoxide production and acyl lipids peroxidation in the thylakoids decreased, prompting upper rates of the Hill and Mehler reactions. Connected to UV-B irradiation, higher accumulated Mn in thylakoids was found to be chelated in a 36.5 kDa protein, with Mn/protein ratio of about 1 and high content of Gln, Asp, Glu, Leu and Gly, being its EPR spectrum characteristic of high-spin Mn(II), in a S=5/2 ground state. As this protein exhibited enzymatic catalysis of superoxide dismutation, it was concluded that, under UV-B irradiation, the high internal tolerance of Oryza sativa L. to Mn during the vegetative growth also triggers the synthesis of a manganese protein that mimics superoxide dismutase functioning, therefore furnishing an additional intimate protection against oxidative stress.
Original languageUnknown
Pages (from-to)457-466
JournalJournal Of Agronomy And Crop Science
Volume200
Issue number6
DOIs
Publication statusPublished - 1 Jan 2014

Keywords

    Cite this

    @article{a4513f06d7e044feaa11413285a06f4f,
    title = "In UV-B irradiated rice high levels of Mn limits chloroplasts injury triggered by oxidative stress",
    abstract = "The molecular mechanism to control the oxidative burst exerted by Mn accumulation in rice (Oryza sativaL.) plants, grown in hydroponics containing 0.5, 2 and 8mgl(-1) Mn and irradiated with a total biological effective UV-B irradiation of 20.825kJm(-2), was investigated in the chloroplasts at the 15th and 21st days after germination. In both experimental periods, Mn accumulation kinetics in the leaves and in the chloroplast lamellae displayed overall increases. Coupled to higher membrane selectivity, superoxide production and acyl lipids peroxidation in the thylakoids decreased, prompting upper rates of the Hill and Mehler reactions. Connected to UV-B irradiation, higher accumulated Mn in thylakoids was found to be chelated in a 36.5 kDa protein, with Mn/protein ratio of about 1 and high content of Gln, Asp, Glu, Leu and Gly, being its EPR spectrum characteristic of high-spin Mn(II), in a S=5/2 ground state. As this protein exhibited enzymatic catalysis of superoxide dismutation, it was concluded that, under UV-B irradiation, the high internal tolerance of Oryza sativa L. to Mn during the vegetative growth also triggers the synthesis of a manganese protein that mimics superoxide dismutase functioning, therefore furnishing an additional intimate protection against oxidative stress.",
    keywords = "Oryza sativa, chloroplast, manganese containing protein, superoxide, manganese accumulation, L, UV-B radiation",
    author = "Lidon, {Fernando Jos{\'e} Cebola}",
    note = "Sem PDF conforme Despacho",
    year = "2014",
    month = "1",
    day = "1",
    doi = "10.1111/jac.12075",
    language = "Unknown",
    volume = "200",
    pages = "457--466",
    journal = "Journal Of Agronomy And Crop Science",
    issn = "0931-2250",
    publisher = "Blackwell Publishing Ltd",
    number = "6",

    }

    TY - JOUR

    T1 - In UV-B irradiated rice high levels of Mn limits chloroplasts injury triggered by oxidative stress

    AU - Lidon, Fernando José Cebola

    N1 - Sem PDF conforme Despacho

    PY - 2014/1/1

    Y1 - 2014/1/1

    N2 - The molecular mechanism to control the oxidative burst exerted by Mn accumulation in rice (Oryza sativaL.) plants, grown in hydroponics containing 0.5, 2 and 8mgl(-1) Mn and irradiated with a total biological effective UV-B irradiation of 20.825kJm(-2), was investigated in the chloroplasts at the 15th and 21st days after germination. In both experimental periods, Mn accumulation kinetics in the leaves and in the chloroplast lamellae displayed overall increases. Coupled to higher membrane selectivity, superoxide production and acyl lipids peroxidation in the thylakoids decreased, prompting upper rates of the Hill and Mehler reactions. Connected to UV-B irradiation, higher accumulated Mn in thylakoids was found to be chelated in a 36.5 kDa protein, with Mn/protein ratio of about 1 and high content of Gln, Asp, Glu, Leu and Gly, being its EPR spectrum characteristic of high-spin Mn(II), in a S=5/2 ground state. As this protein exhibited enzymatic catalysis of superoxide dismutation, it was concluded that, under UV-B irradiation, the high internal tolerance of Oryza sativa L. to Mn during the vegetative growth also triggers the synthesis of a manganese protein that mimics superoxide dismutase functioning, therefore furnishing an additional intimate protection against oxidative stress.

    AB - The molecular mechanism to control the oxidative burst exerted by Mn accumulation in rice (Oryza sativaL.) plants, grown in hydroponics containing 0.5, 2 and 8mgl(-1) Mn and irradiated with a total biological effective UV-B irradiation of 20.825kJm(-2), was investigated in the chloroplasts at the 15th and 21st days after germination. In both experimental periods, Mn accumulation kinetics in the leaves and in the chloroplast lamellae displayed overall increases. Coupled to higher membrane selectivity, superoxide production and acyl lipids peroxidation in the thylakoids decreased, prompting upper rates of the Hill and Mehler reactions. Connected to UV-B irradiation, higher accumulated Mn in thylakoids was found to be chelated in a 36.5 kDa protein, with Mn/protein ratio of about 1 and high content of Gln, Asp, Glu, Leu and Gly, being its EPR spectrum characteristic of high-spin Mn(II), in a S=5/2 ground state. As this protein exhibited enzymatic catalysis of superoxide dismutation, it was concluded that, under UV-B irradiation, the high internal tolerance of Oryza sativa L. to Mn during the vegetative growth also triggers the synthesis of a manganese protein that mimics superoxide dismutase functioning, therefore furnishing an additional intimate protection against oxidative stress.

    KW - Oryza sativa

    KW - chloroplast

    KW - manganese containing protein

    KW - superoxide

    KW - manganese accumulation

    KW - L

    KW - UV-B radiation

    U2 - 10.1111/jac.12075

    DO - 10.1111/jac.12075

    M3 - Article

    VL - 200

    SP - 457

    EP - 466

    JO - Journal Of Agronomy And Crop Science

    JF - Journal Of Agronomy And Crop Science

    SN - 0931-2250

    IS - 6

    ER -