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Makoto Kusaba - One of the best experts on this subject based on the ideXlab platform.

  • Two short-chain dehydrogenase/reductases, NON-YELLOW COLORING 1 and NYC1-LIKE, are required for chlorophyll b and Light-Harvesting Complex II degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Susumu Katsuma, Makoto Kusaba
    Abstract:

    Yellowing, which is related to the degradation of chlorophyll and chlorophyll-protein Complexes, is a notable phenomenon during leaf senescence. NON-YELLOW COLORING 1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the stay-green phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.

  • two short chain dehydrogenase reductases non yellow coloring 1 and nyc1 like are required for chlorophyll b and light harvesting Complex ii degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Makoto Kusaba, Susumu Katsuma
    Abstract:

    *† Summary Yellowing, which is related to the degradation of chlorophyll and chlorophyll–protein Complexes, is a notable phenomenon during leaf senescence.NON-YELLOW COLORING1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the staygreen phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.

Yutaka Sato - One of the best experts on this subject based on the ideXlab platform.

  • Two short-chain dehydrogenase/reductases, NON-YELLOW COLORING 1 and NYC1-LIKE, are required for chlorophyll b and Light-Harvesting Complex II degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Susumu Katsuma, Makoto Kusaba
    Abstract:

    Yellowing, which is related to the degradation of chlorophyll and chlorophyll-protein Complexes, is a notable phenomenon during leaf senescence. NON-YELLOW COLORING 1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the stay-green phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.

  • two short chain dehydrogenase reductases non yellow coloring 1 and nyc1 like are required for chlorophyll b and light harvesting Complex ii degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Makoto Kusaba, Susumu Katsuma
    Abstract:

    *† Summary Yellowing, which is related to the degradation of chlorophyll and chlorophyll–protein Complexes, is a notable phenomenon during leaf senescence.NON-YELLOW COLORING1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the staygreen phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.

Egbert J Boekema - One of the best experts on this subject based on the ideXlab platform.

  • functional analyses of the plant photosystem i light harvesting Complex ii superComplex reveal that light harvesting Complex ii loosely bound to photosystem ii is a very efficient antenna for photosystem i in state ii
    The Plant Cell, 2012
    Co-Authors: Pierre Galka, Egbert J Boekema, Stefano Santabarbara, Thi Thu Khuong Khuong, Herve Degand, Pierre Morsomme, Robert C Jennings, Stefano Caffarri
    Abstract:

    State transitions are an important photosynthetic short-term response that allows energy distribution balancing between photosystems I (PSI) and II (PSII). In plants when PSII is preferentially excited compared with PSI (State II), part of the major Light-Harvesting Complex LHCII migrates to PSI to form a PSI-LHCII superComplex. So far, little is known about this Complex, mainly due to purification problems. Here, a stable PSI-LHCII superComplex is purified from Arabidopsis thaliana and maize (Zea mays) plants. It is demonstrated that LHCIIs loosely bound to PSII in State I are the trimers mainly involved in state transitions and become strongly bound to PSI in State II. Specific Lhcb1-3 isoforms are differently represented in the mobile LHCII compared with S and M trimers. Fluorescence analyses indicate that excitation energy migration from mobile LHCII to PSI is rapid and efficient, and the quantum yield of photochemical conversion of PSI-LHCII is substantially unaffected with respect to PSI, despite a sizable increase of the antenna size. An updated PSI-LHCII structural model suggests that the lowenergy chlorophylls 611 and 612 in LHCII interact with the chlorophyll 11145 at the interface of PSI. In contrast with the common opinion, we suggest that the mobile pool of LHCII may be considered an intimate part of the PSI antenna system that is displaced to PSII in State I.

  • lack of the light harvesting Complex cp24 affects the structure and function of the grana membranes of higher plant chloroplasts
    The Plant Cell, 2006
    Co-Authors: Laszlo Kovacs, Egbert J Boekema, Stefan Jansson, Jakob T Damkjaer, Sami Kereiche, Cristian Ilioaia, Alexander V Ruban, Peter Horton
    Abstract:

    The photosystem II (PSII) Light-Harvesting antenna in higher plants contains a number of highly conserved gene products whose function is unknown. Arabidopsis thaliana plants depleted of one of these, the CP24 Light-Harvesting Complex, have been analyzed. CP24-deficient plants showed a decrease in light-limited photosynthetic rate and growth, but the pigment and protein content of the thylakoid membranes were otherwise almost unchanged. However, there was a major change in the macroorganization of PSII within these membranes; electron microscopy and image analysis revealed the complete absence of the C2S2M2 Light-Harvesting Complex II (LHCII)/PSII superComplex predominant in wild-type plants. Instead, only C2S2 superComplexes, which are deficient in the LHCIIb M-trimers, were found. Spectroscopic analysis confirmed the disruption of the wild-type macroorganization of PSII. It was found that the functions of the PSII antenna were disturbed: connectivity between PSII centers was reduced, and maximum photochemical yield was lowered; rapidly reversible nonphotochemical quenching was inhibited; and the state transitions were altered kinetically. CP24 is therefore an important factor in determining the structure and function of the PSII Light-Harvesting antenna, providing the linker for association of the M-trimer into the PSII Complex, allowing a specific macroorganization that is necessary both for maximum quantum efficiency and for photoprotective dissipation of excess excitation energy.

  • Supramolecular organization of photosystem I and light‐harvesting Complex I in Chlamydomonas reinhardtii
    FEBS Letters, 2002
    Co-Authors: Marta Germano, Jan P Dekker, Alevtyna E Yakushevska, Wilko Keegstra, Hans J Van Gorkom, Egbert J Boekema
    Abstract:

    We report a structural characterization by electron microscopy and image analysis of a supramolecular Complex consisting of photosystem I and Light-Harvesting Complex I from the unicellular green alga Chlamydomonas reinhardtii. The Complex is a monomer, has longest dimensions of 21.3 and 18.2 nm in projection, and is significantly larger than the corresponding Complex in spinach. Comparison with photosystem I Complexes from other organisms suggests that the Complex contains about 14 Light-Harvesting proteins, two or three of which bind at the side of the PSI-H subunit. We suggest that special Light-Harvesting I proteins play a role in the binding of phosphorylated Light-Harvesting Complex II in state 2.

  • Supramolecular organization of photosystem I and Light-Harvesting Complex I in Chlamydomonas reinhardtii.
    FEBS letters, 2002
    Co-Authors: Marta Germano, Jan P Dekker, Alevtyna E Yakushevska, Wilko Keegstra, Hans J Van Gorkom, Egbert J Boekema
    Abstract:

    We report a structural characterization by electron microscopy and image analysis of a supramolecular Complex consisting of photosystem I and Light-Harvesting Complex I from the unicellular green alga Chlamydomonas reinhardtii. The Complex is a monomer, has longest dimensions of 21.3 and 18.2 nm in projection, and is significantly larger than the corresponding Complex in spinach. Comparison with photosystem I Complexes from other organisms suggests that the Complex contains about 14 Light-Harvesting proteins, two or three of which bind at the side of the PSI-H subunit. We suggest that special Light-Harvesting I proteins play a role in the binding of phosphorylated Light-Harvesting Complex II in state 2.

  • Specific association of photosystem II and Light-Harvesting Complex II in partially solubilized photosystem II membranes
    FEBS Letters, 1998
    Co-Authors: Egbert J Boekema, Henny Van Roon, Jan P Dekker
    Abstract:

    In this study, we report the structural characterization of photosystem II Complexes obtained from partially solubilized photosystem II membranes. Direct observation by electron microscopy, within a few minutes after a mild disruption of the membranes with the detergent n-dodecyl-α,d-maltoside, revealed the presence of several large supramolecular Complexes. Images of these Complexes were subjected to multivariate statistical analysis and classification procedures, resolving a new Complex consisting of the previously characterized dimeric superComplex of photosystem II and Light-Harvesting Complex II [Boekema et al., Proc. Natl. Acad. Sci. USA 92 (1995) 175–179] and two additional, symmetrically organized protein masses each containing a second type of trimeric Light-Harvesting II Complex. We conclude that large and labile integral membrane proteins, such as photosystem II, can be quickly structurally characterized without extensive purification.

Harald Paulsen - One of the best experts on this subject based on the ideXlab platform.

  • Bio serves nano: Biological Light-Harvesting Complex as energy donor for semiconductor quantum dots
    Langmuir, 2012
    Co-Authors: Mara Werwie, Xiangxing Xu, Mathias Haase, Thomas Basche, Harald Paulsen
    Abstract:

    Light-Harvesting Complex (LHCII) of the photosynthetic apparatus in plants is attached to type-II core-shell CdTe/CdSe/ZnS nanocrystals (quantum dots, QD) exhibiting an absorption band at 710 nm and carrying a dihydrolipoic acid coating for water solubility. LHCII stays functional upon binding to the QD surface and enhances the light utilization of the QDs significantly, similar to its Light-Harvesting function in photosynthesis. Electronic excitation energy transfer of about 50% efficiency is shown by donor (LHCII) fluorescence quenching as well as sensitized acceptor (QD) emission and corroborated by time-resolved fluorescence measurements. The energy transfer efficiency is commensurable with the expected efficiency calculated according to Förster theory on the basis of the estimated donor-acceptor separation. Light harvesting is particularly efficient in the red spectral domain where QD absorption is relatively low. Excitation over the entire visible spectrum is further improved by complementing the biological pigments in LHCII with a dye attached to the apoprotein; the dye has been chosen to absorb in the "green gap" of the LHCII absorption spectrum and transfers its excitation energy ultimately to QD. This is the first report of a biological Light-Harvesting Complex serving an inorganic semiconductor nanocrystal. Due to the charge separation between the core and the shell in type-II QDs the presented LHCII-QD hybrid Complexes are potentially interesting for sensitized charge-transfer and photovoltaic applications. © 2012 American Chemical Society.

  • Site-specific incorporation of perylene into an N-terminally modified Light-Harvesting Complex II
    Organic and Biomolecular Chemistry, 2010
    Co-Authors: Kalina Peneva, Harald Paulsen, Kristina Gundlach, Andreas Herrmann, Klaus Müllen
    Abstract:

    Employing the utility of the native chemical ligation, site-specific attachment of an ultrastable perylene dye to a derivative of the major Light-Harvesting Complex (LHCII) was demonstrated. Biochemical analysis of the conjugate indicated that the structure and function of LHCII remain largely unaffected by the N-terminal modification.

  • Assemblies of semiconductor quantum dots and Light-Harvesting-Complex II
    Journal of Luminescence, 2010
    Co-Authors: Wolfgang Erker, Harald Paulsen, Stephanie Boggasch, Götz Grundmann, Thomas Basche
    Abstract:

    Abstract A novel hybrid system composed of fluorescent core/shell semiconductor quantum dots and the light harvesting Complex II (LHCIIb), a membrane protein of higher plants, has been assembled. Experiments with different mutants show that hybrid formation can be mediated by a C-terminal His 6 tag attached to the protein as well as by positive charges of the first N-terminal amino acids of LHCIIb. Quenching of the quantum dot fluorescence upon binding of LHCIIb was partially attributed to energy transfer from the quantum dots to LHCIIb.

Ryouhei Morita - One of the best experts on this subject based on the ideXlab platform.

  • Two short-chain dehydrogenase/reductases, NON-YELLOW COLORING 1 and NYC1-LIKE, are required for chlorophyll b and Light-Harvesting Complex II degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Susumu Katsuma, Makoto Kusaba
    Abstract:

    Yellowing, which is related to the degradation of chlorophyll and chlorophyll-protein Complexes, is a notable phenomenon during leaf senescence. NON-YELLOW COLORING 1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the stay-green phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.

  • two short chain dehydrogenase reductases non yellow coloring 1 and nyc1 like are required for chlorophyll b and light harvesting Complex ii degradation during senescence in rice
    Plant Journal, 2009
    Co-Authors: Yutaka Sato, Ryouhei Morita, Minoru Nishimura, Ayumi Tanaka, Makoto Kusaba, Susumu Katsuma
    Abstract:

    *† Summary Yellowing, which is related to the degradation of chlorophyll and chlorophyll–protein Complexes, is a notable phenomenon during leaf senescence.NON-YELLOW COLORING1 (NYC1) in rice encodes a membrane-localized short-chain dehydrogenase/reductase (SDR) that is thought to represent a chlorophyll b reductase necessary for catalyzing the first step of chlorophyll b degradation. Analysis of the nyc1 mutant, which shows the staygreen phenotype, revealed that chlorophyll b degradation is required for the degradation of Light-Harvesting Complex II and thylakoid grana in leaf senescence. Phylogenetic analysis further revealed the existence of NYC1-LIKE (NOL) as the most closely related protein to NYC1. In the present paper, the nol mutant in rice was also found to show a stay-green phenotype very similar to that of the nyc1 mutant, i.e. the degradation of chlorophyll b was severely inhibited and Light-Harvesting Complex II was selectively retained during senescence, resulting in the retention of thylakoid grana even at a late stage of senescence. The nyc1 nol double mutant did not show prominent enhancement of inhibition of chlorophyll degradation. NOL was localized on the stromal side of the thylakoid membrane despite the lack of a transmembrane domain. Immunoprecipitation analysis revealed that NOL and NYC1 interact physically in vitro. These observations suggest that NOL and NYC1 are co-localized in the thylakoid membrane and act in the form of a Complex as a chlorophyll b reductase in rice.