Identification of a functional respiratory complex in chloroplasts through analysis of tobacco mutants containing disrupted plastid ndh genes

The plastid genomes of several plants contain homologues, termed ndh genes, of genes encoding subunits of the NADH:ubiquinone oxidoreductase or complex I of mitochondria and eubacteria. The functional significance of the Ndh proteins in higher plants is uncertain. We show here that tobacco chloroplasts contain a protein complex of 550 kDa consisting of at least three of the ndh gene products: NdhI, NdhJ and NdhK. We have constructed mutant tobacco plants with disrupted ndhC, ndhK and ndhJ plastid genes, indicating that the Ndh complex is dispensible for plant growth under optimal growth conditions. Chlorophyll fluorescence analysis shows that in vivo the Ndh complex catalyses the post‐illumination reduction of the plastoquinone pool and in the light optimizes the induction of photosynthesis under conditions of water stress. We conclude that the Ndh complex catalyses the reduction of the plastoquinone pool using stromal reductant and so acts as a respiratory complex. Overall, our data are compatible with the participation of the Ndh complex in cyclic electron flow around the photosystem I complex in the light and possibly in a chloroplast respiratory chain in the dark.

[1]  U. Heber.  Metabolite Exchange Between Chloroplasts and Cytoplasm , 1974 .

[2]  T. White,et al.  Characterization of Three Related Low-Temperature-Regulated cDNAs from Winter Brassica napus , 1993, Plant physiology.

[3]  L. Casano,et al.  Identification of the product of ndhA gene as a thylakoid protein synthesized in response to photooxidative treatment. , 1996, Plant & cell physiology.

[4]  P. Nixon,et al.  Detection and characterization of a complex I-like NADH-specific dehydrogenase from pea thylakoids. , 1996, Biochemical Society transactions.

[5]  P. Horton,et al.  Regulation of Light Harvesting in Green Plants (Indication by Nonphotochemical Quenching of Chlorophyll Fluorescence) , 1994, Plant physiology.

[6]  K. Asada,et al.  Electron donation from cyclic and respiratory flows to the photosynthetic intersystem chain is mediated by pyridine nucleotide dehydrogenase in the cyanobacterium Synechocystis PCC 6803 , 1992 .

[7]  T. Friedrich,et al.  The proton‐pumping respiratory complex I of bacteria and mitochondria and its homologue in chloroplasts , 1995, FEBS letters.

[8]  P. Gans,et al.  ATP control on state transitions in vivo in Chlamydomonas reinhardtii , 1990 .

[9]  H. Schägger,et al.  Analysis of molecular masses and oligomeric states of protein complexes by blue native electrophoresis and isolation of membrane protein complexes by two-dimensional native electrophoresis. , 1994, Analytical biochemistry.

[10]  F. Takaiwa,et al.  The complete nucleotide sequence of the tobacco chloroplast genome: its gene organization and expression , 1986, The EMBO journal.

[11]  C. Yocum,et al.  Evidence for two cyclic photophosphorylation reactions concurrent with ferredoxin-catalyzed non-cyclic electron transport , 1985 .

[12]  K. Asada,et al.  Thylakoid Membrane-Bound, NADPH-Specific Pyridine Nucleotide Dehydrogenase Complex Mediates Cyclic Electron Transport in the Cyanobacterium Synechocystis sp. PCC 6803 , 1995 .

[13]  T. Friedrich,et al.  Isolation and characterization of the proton-translocating NADH: ubiquinone oxidoreductase from Escherichia coli. , 1995, European journal of biochemistry.

[14]  P. Nixon,et al.  The plastid ndh genes code for an NADH-specific dehydrogenase: isolation of a complex I analogue from pea thylakoid membranes. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[15]  D. Bendall,et al.  Cyclic photophosphorylation and electron transport , 1995 .

[16]  U. Heber,et al.  Concerning a dual function of coupled cyclic electron transport in leaves. , 1992, Plant physiology.

[17]  S. Cuiné,et al.  Evidence for an association of ndh B, ndh J gene products and ferredoxin‐NADP‐reductase as components of a chloroplastic NAD(P)H dehydrogenase complex , 1996, FEBS letters.

[18]  J. Walker,et al.  Conservation of sequences of subunits of mitochondrial complex I and their relationships with other proteins. , 1992, Biochimica et biophysica acta.

[19]  A. Melis,et al.  Dynamics of photosynthetic membrane composition and function , 1991 .

[20]  J. Mano,et al.  Photoactivation of the Electron Flow from NADPH to Plastoquinone in Spinach Chloroplasts , 1995 .

[21]  psbG is not a photosystem two gene but may be an ndh gene. , 1989, The Journal of biological chemistry.

[22]  K. Steinback,et al.  Chloroplast protein phosphorylation couples plastoquinone redox state to distribution of excitation energy between photosystems , 1981, Nature.

[23]  G. Krause,et al.  Chlorophyll Fluorescence and Photosynthesis: The Basics , 1991 .

[24]  J. Barber,et al.  Photoinduced degradation of the D1 polypeptide in isolated reaction centers of photosystem II: evidence for an autoproteolytic process triggered by the oxidizing side of the photosystem. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[25]  P. Horton,et al.  REGULATION OF LIGHT HARVESTING IN GREEN PLANTS. , 1996, Annual review of plant physiology and plant molecular biology.

[26]  P. Bennoun.  Chlororespiration revisited: Mitochondrial-plastid interactions in Chlamydomonas , 1994 .

[27]  P. Maliga,et al.  Stable transformation of plastids in higher plants. , 1990, Proceedings of the National Academy of Sciences of the United States of America.

[28]  T. Kohchi,et al.  Chloroplast gene organization deduced from complete sequence of liverwort Marchantia polymorpha chloroplast DNA , 1986, Nature.

[29]  M. Stitt,et al.  An Examination of Factors Contributing to Non-Photochemical Quenching of Chlorophyll Fluorescence in Barley Leaves , 1989 .

[30]  J. Biggins,et al.  Role of cyclic electron transport in photosynthesis as measured by the photoinduced turnover of P700 in vivo. , 1976, Biochemistry.

[31]  J. Zhao,et al.  PsaE Is Required for in Vivo Cyclic Electron Flow around Photosystem I in the Cyanobacterium Synechococcus sp. PCC 7002 , 1993, Plant physiology.

[32]  G. Harris,et al.  Effects of Anaerobiosis on Chlorophyll Fluorescence Yield in Spinach (Spinacia oleracea) Leaf Discs , 1993, Plant physiology.

[33]  U. Schreiber,et al.  Measuring P700 Absorbance Changes around 830 nm with a New Type of Pulse Modulation System , 1988 .

[34]  P. Maliga,et al.  High-frequency plastid transformation in tobacco by selection for a chimeric aadA gene. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[35]  B. Diner.  Dependence of the deactivation reactions of photosystem II on the redox state of plastoquinone pool A varied under anaerobic conditions; Equilibria on the acceptor side of photosystem II. , 1977, Biochimica et biophysica acta.

[36]  D. Arnon.  COPPER ENZYMES IN ISOLATED CHLOROPLASTS. POLYPHENOLOXIDASE IN BETA VULGARIS. , 1949, Plant physiology.

[37]  P. Bennoun.  Evidence for a respiratory chain in the chloroplast. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[38]  W. Plaxton,et al.  THE ORGANIZATION AND REGULATION OF PLANT GLYCOLYSIS. , 1996, Annual review of plant physiology and plant molecular biology.