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Modification of the endogenous NO level influences apple embryos dormancy by alterations of nitrated and biotinylated protein patterns

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Abstract

Main conclusion

NO donors and Arg remove dormancy of apple embryos and stimulate germination. Compounds lowering NO level (cPTIO, L -NAME, CAN) strengthen dormancy. Embryo transition from dormancy state to germination is linked to increased nitric oxide synthase (NOS)-like activity. Germination of embryos is associated with declined level of biotin containing proteins and nitrated proteins in soluble protein fraction of root axis. Pattern of nitrated proteins suggest that storage proteins are putative targets of nitration.

Nitric oxide (NO) acts as a key regulatory factor in removal of seed dormancy and is a signal necessary for seed transition from dormant state into germination. Modulation of NO concentration in apple (Malus domestica Borkh.) embryos by NO fumigation, treatment with NO donor (S-nitroso-N-acetyl-d,l-penicillamine, SNAP), application of 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), N ω-nitro-l-arginine methyl ester (l-NAME), canavanine (CAN) or arginine (Arg) allowed us to investigate the NO impact on seed dormancy status. Arg analogs and NO scavenger strengthened embryo dormancy by lowering reactive nitrogen species level in embryonic axes. This effect was accompanied by strong inhibition of NOS-like activity, without significant influence on tissue NO2 − concentration. Germination sensu stricto of apple embryos initiated by dormancy breakage via short term NO treatment or Arg supplementation were linked to a reduced level of biotinylated proteins in root axis. Decrease of total soluble nitrated proteins was observed at the termination of germination sensu stricto. Also modulation of NO tissue status leads to modification in nitrated protein pattern. Among protein bands that correspond to molecular mass of approximately 95 kDa, storage proteins (legumin A-like and seed biotin-containing protein) were identified, and can be considered as good markers for seed dormancy status. Moreover, pattern of nitrated proteins suggest that biotin containing proteins are also targets of nitration.

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Abbreviations

3-NT:

3-Nitro-tyrosine

CAN:

Canavanine

cPTIO:

2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide

BH4 :

6R-Tetra-hydrobiopterin

l-NAME:

N ω-Nitro-l-arginine methyl ester

NO:

Nitric oxide

NOS:

Nitric oxide synthase

RNS:

Reactive nitrogen species

ROS:

Reactive oxygen species

SIN-1:

3-Morpholinosydnonimine

SNAP:

S-Nitroso-N-acetyl-d,l-penicillamine

SNP:

Sodium nitroprusside

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Acknowledgments

Part of the work was financed by National Science Centre Poland Grant no. NN 303821840.

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Authors and Affiliations

  1. Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland

    Urszula Krasuska, Katarzyna Ciacka, Renata Bogatek & Agnieszka Gniazdowska

  2. Department of Biochemistry, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland

    Sławomir Orzechowski

  3. Biopolymer Analytics, University of Potsdam, Karl-Liebknecht 24-25, 14476, Potsdam-Golm, Germany

    Joerg Fettke

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  1. Urszula Krasuska
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  2. Katarzyna Ciacka
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  6. Agnieszka Gniazdowska
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Correspondence to Agnieszka Gniazdowska.

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Supplementary Fig. S1 Embryos or seedlings developed from dormant apple embryos (control), from dormant embryos pre-treated with vapors of acidified NO2 − (NO), SNAP, SIN-1, or imbibed in Arg, cPTIO, l-NAME, CAN and uric acid after 8 days of germination period. Photographs are representative of the samples (PDF 144 kb)

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Krasuska, U., Ciacka, K., Orzechowski, S. et al. Modification of the endogenous NO level influences apple embryos dormancy by alterations of nitrated and biotinylated protein patterns. Planta 244, 877–891 (2016). https://doi.org/10.1007/s00425-016-2553-z

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