Dual targeted poplar ferredoxin NADP+ oxidoreductase interacts with hemoglobin 1. (June 2016)

• Record Type: Journal Article
• Authors: Jokipii-Lukkari, Soile; Kastaniotis, Alexander J.; Parkash, Vimal; Sundström, Robin; Leiva-Eriksson, Nélida; Nymalm, Yvonne; Blokhina, Olga; Kukkola, Eija; Fagerstedt, Kurt V.; Salminen, Tiina A.; Läärä, Esa; Bülow, Leif; Ohlmeier, Steffen; Hiltunen, J. Kalervo; Kallio, Pauli T.; Häggman, Hely
• Is Part Of: Plant science. Volume 247(2016:Jun.)
• Page Start: 138
• Page End: 149
• Publication Date: 2016-06
• Subjects: BCIP/NPT 5-bromo-4-chloro-3-indolylphosphate/nitroblue tetrazolium -- BiFC bimolecular fluorescence complementation -- 2-DE two-dimensional gel electrophoresis -- DETA NONOate (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1, 2-diolate -- DIG digoxigenin -- Hbs hemoglobins -- hFNR heterotrophic ferredoxin NADP+ oxidoreductase -- MS mass spectrometry -- NO nitric oxide -- NOD NO dioxygenation -- nsHb non-symbiotic hemoglobin -- ORF open reading frame -- PIPES piparazine-N, N'-bis(ethanesulfonic acid) -- PMF Peptide Mass Fingerprint -- RACE rapid amplification of cDNA ends -- SNP sodium nitroprusside -- trHb truncated hemoglobin -- WT wild-type; Dioxygenation -- Dual targeting -- Ferredoxin NADP+ oxidoreductase -- Hemoglobin -- Nitric oxide -- Poplar; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2016.03.013
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: A novel cytosolic root-type ferredoxin NADP + oxidoreductase (hFNR) was found. HFNR was able to interact with Hb1 and relieve NO toxicity in living cells. The coexpression of hFNR and truncated Hb did not affect NO sensitivity of cells. This is a first report on dual targeting of plant hFNR to both plastids and cytosol. The result may help to explain the protein dual targeting phenomenon. Abstract: 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 ) Δ yhb1 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 Δ yhb1 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.