Dual targeted poplar ferredoxin NADP(+) oxidoreductase interacts with hemoglobin 1.
Previous reports have connected non-symbiotic and truncated hemoglobins (Hbs) to metabolism of nitric oxide (NO), an important signalling molecule involved in wood formation. We have studied the capability of poplar (Populus tremula × tremuloides) Hbs PttHb1 and PttTrHb proteins alone or with a flavin-protein reductase to relieve NO cytotoxicity in living cells. Complementation tests in a Hb-deficient, NO-sensitive yeast (Saccharomyces cerevisiae) Δyhb1 mutant showed that neither PttHb1 nor PttTrHb alone protected cells against NO. To study the ability of Hbs to interact with a reductase, ferredoxin NADP(+) oxidoreductase PtthFNR was characterized by sequencing and proteomics. To date, by far the greatest number of the known dual-targeted plant proteins are directed to chloroplasts and mitochondria. We discovered a novel variant of hFNR that lacks the plastid presequence and resides in cytosol. The coexpression of PttHb1 and PtthFNR partially restored NO resistance of the yeast Δyhb1 mutant, whereas PttTrHb coexpressed with PtthFNR failed to rescue growth. YFP fusion proteins confirmed the interaction between PttHb1 and PtthFNR in plant cells. The structural modelling results indicate that PttHb1 and PtthFNR are able to interact as NO dioxygenase. This is the first report on dual targeting of central plant enzyme FNR to plastids and cytosol.
Genetics and Physiology Department, University of Oulu, P.O. Box 3000, FI-90014, Finland.
Soile
S
Jokipii-Lukkari
The Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu, University of Oulu, P.O. Box 5400, FI-90014, Finland.
Alexander J
AJ
Kastaniotis
The Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland.
Vimal
V
Parkash
The Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland.
Robin
R
Sundström
The Pure and Applied Biochemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Nélida
N
Leiva-Eriksson
The Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland.
Yvonne
Y
Nymalm
The Department of Biosciences, University of Helsinki, Viikki Biocenter 3, P.O. Box 65, FI-00014, Finland.
Olga
O
Blokhina
The Department of Biosciences, University of Helsinki, Viikki Biocenter 3, P.O. Box 65, FI-00014, Finland.
Eija
E
Kukkola
The Department of Biosciences, University of Helsinki, Viikki Biocenter 3, P.O. Box 65, FI-00014, Finland.
Kurt V
KV
Fagerstedt
The Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland.
Tiina A
TA
Salminen
The Department of Mathematical Sciences, University of Oulu, P.O. Box 3000, FI-90014, Finland.
Esa
E
Läärä
The Pure and Applied Biochemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Leif
L
Bülow
The Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu, University of Oulu, P.O. Box 5400, FI-90014, Finland.
Steffen
S
Ohlmeier
The Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu, University of Oulu, P.O. Box 5400, FI-90014, Finland.
J Kalervo
JK
Hiltunen
The Institute of Microbiology, ETH-Zürich, CH-8093 Zürich, Switzerland.
Pauli T
PT
Kallio
Genetics and Physiology Department, University of Oulu, P.O. Box 3000, FI-90014, Finland. Electronic address: hely.haggman@oulu.fi.
Hely
H
Häggman
D002736:Chloroplasts / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D005287:Ferredoxin-NADP Reductase / Q000235:genetics / Q000378:metabolism*; D017930:Genes, Reporter; D006454:Hemoglobins / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D009154:Mutation; D009569:Nitric Oxide / Q000494:pharmacology*; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D032107:Populus / Q000201:enzymology* / Q000235:genetics; D040901:Proteomics; D011993:Recombinant Fusion Proteins; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D017422:Sequence Analysis, DNA
D006454:Hemoglobins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D009569:Nitric Oxide; D010105:Oxygenases; C114415:nitric oxide dioxygenase; D005287:Ferredoxin-NADP Reductase
Dioxygenation; Dual targeting; Ferredoxin NADP(+) oxidoreductase; Hemoglobin; Nitric oxide; Poplar