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  • 1 Mansoura University, Mansoura, Egypt
  • 2 Kafr El Sheikh University, Kafr El Sheikh, Egypt
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This study is aimed to investigate the activity of urease (EC 3.5.1.5, urea amidohydrolase) that catalyzes the hydrolysis of urea in 5-day-old Cucurbita pepo cotyledons subjected to various concentrations of different growth regulators. The treatment of C. pepo cotyledons with different concentrations (100–600 μmol) of different auxins [indole-3-acetic acid (IAA), indole butyric acid (IBA), indole propionic acid (IPA) and naphthalene acetic acid (NAA)]; or with different concentrations (100–300 μmol) of different cytokinins [kinetin, zeatin and benzyladenine (6-BA)] resulted in a significant increase of urease activity, compared to control. The optimal effects were recorded for each of 500 μmol of IAA and 300 μmol of zeatin treatments. A gradual increase in urease activity was detected in cotyledons treated with various concentrations (0.2–1.0 mM) of 28-homobrassinolide (HBL), in relative to control. A substantial increase in urease activity was observed in cotyledons subjected to different concentrations of triazole (10–60 mg L–1), containing either triadimefon (TDM) or hexaconazole (HEX), compared to control. The combination of 300 μmol zeatin with any of protein inhibitors, namely 5-fluorouridine (FUrd), cordycepin and α-amanitin, resulted in the alleviation of their inhibitory effect on the urease activity.

  • 1.

    Ali, B., Hayat, S., Ahmad, A. (2007) 28-Homobrassinosteroids ameliorates the saline stress in Cicer arietinum L. Environ. Exp. Bot. 59, 217223.

    • Search Google Scholar
    • Export Citation
  • 2.

    Ananiev, E. D., Abdulova, G., Grozdanov, P., Karagyozov, L. (2003) Hormonal regulation of ribosomal RNA gene expression in excised cotyledons of Cucurbita pepo L. (zucchini). Bulg. J. PlantPhysiol. SI. 225231.

    • Search Google Scholar
    • Export Citation
  • 3.

    Awasthi, V., Garg, S. K. (2007) Effect of salicylic acid on enzymes of ammonium assimilation in maize seedling. Indian J. Plant Physiol. 12, 391393.

    • Search Google Scholar
    • Export Citation
  • 4.

    Bajguz, A., Piotrowska, A. (2009) Conjugates of auxin and cytokinin. Phytochemistry 70, 957969.

  • 5.

    Buchnauer, H., Röhner, E. (1981) Effect of triadimefon and triadimenol on growth of various plant species as well as on gibberellin content and sterol metabolism in shoots of barley seedlings. PesticideBioch. Physiol. 15, 5870.

    • Search Google Scholar
    • Export Citation
  • 6.

    Cavariani, C., Velini, E. D., Bicudo, S. J., Nakagawa, J. (1994) Avaliação dos efeitos de doses de triadimenol e de tebuconazole sobre o crescimento do mesocótilo em plântulas de trigo. Pesq AgropecBras. 29, 10351039.

    • Search Google Scholar
    • Export Citation
  • 7.

    Chung, H. H., Chen, J. T., Chang, W. C. (2007) Plant regeneration through direct somatic embryogenesis from leaf explants of Dendrobium. Biol. Plant. 51, 346350.

    • Search Google Scholar
    • Export Citation
  • 8.

    Ciurli, S., Benini, S., Rypniewski, W., Wilson, K. S., Miletti, S., Mangani, S. (1999) Structural properties of the nickel ion in urease: novel insights into the catalytic and inhibition mechanism. Coordination Chem. Rev. 190–192, 331355.

    • Search Google Scholar
    • Export Citation
  • 9.

    Cohen, J. D., Bandurski, R. S. (1982) Chemistry and physiology of the bound auxins. Annu. Rev. Plant Physiol. 33, 403430.

  • 10.

    Cooke, R. M., Durand, R., Job, C., Penon, P., Mteissere, Job, D. (1984) Enzymatic properties of plant RNA polymerases. Plant Mol. Biol. 3, 217225.

    • Search Google Scholar
    • Export Citation
  • 11.

    Datte, K., Marsh, L., Marcus, A. (1983) Early growth of wheat embryonic axes and the synthesis of RNA and DNA. Plant Physiol. 72, 394397.

    • Search Google Scholar
    • Export Citation
  • 12.

    Davies, P. J. (2010) The plant hormones: their nature, occurrence, and functions. Plant Hormones A: 115.

  • 13.

    Dixon, N. E., Gazzola, T. C., Blakeley, R. L., Zermer, B. (1975) Jack bean urease (EC 3.5.1.5). A metalloenzyme. A simple biological role for nickel? J. Am. Chem. Soc. 97, 41314133.

    • Search Google Scholar
    • Export Citation
  • 14.

    El-Shora, H. M. (2001) Effect of growth regulators and group-modifiers on NADH-glutamate synthase of marrow cotyledons. J. Biol. Sci. 1, 597602.

    • Search Google Scholar
    • Export Citation
  • 15.

    El-Shora, H. M., ap Rees, T. (1991) Intracellular location of NADP-linked malic enzymes in C3 plants. Planta 185, 362367.

  • 16.

    Fletcher, R. A., Arnold, V. (1986) Stimulation of cytokinins and chlorophyll synthesis in cucumber cotyledons by triadimefon. Physiol. Plant. 66, 197201.

    • Search Google Scholar
    • Export Citation
  • 17.

    Fletcher, R. A., Hofstra, G. (1988) Triazoles as potential plant protectants. In: Berg, D., Plemple, M. (eds), Sterol biosynthesis inhibitors. Ellis Horwood Ltd., Cambridge, pp. 321331.

    • Search Google Scholar
    • Export Citation
  • 18.

    Gao, J., Hofstra, G., Fletcher, R. A. (1988) Anatomical changes induced by triazoles in wheat seedlings. Canad. J. Bot. 66, 11781185.

    • Search Google Scholar
    • Export Citation
  • 19.

    Holtorf, H., Schöb, H., Kunz, C., Waldvogel, R., Meins, F. Jr. (1999) Stochastic and nonstochastic post-transcriptional silencing of chitinase and ß-1,3-glucanase genes involves increased RNA turnover. A possible role for ribosome independent RNA degradation. Plant Cell 11, 471484.

    • Search Google Scholar
    • Export Citation
  • 20.

    Hongthongkham, J., Bunnag, S. (2014) In vitro propagation and cryopreservation of Aerides odorata Lour. Orchidaceae). Pak. J. Biol. Sci. 17, 608618.

    • Search Google Scholar
    • Export Citation
  • 21.

    Jain, V., Abrol, Y. P. (2005) Regulation of nitrate reductase activity by phytohormones in wheat. J. Plant Biol. 32, 4348.

  • 22.

    Jaleel, C. A., Gopi, R., Alagu Lakshmanan, G. M., Panneerselvam, R. (2006) Triadimefon induced changes in the antioxidant metabolism and ajmalicine production in Catharanthus roseus (L.) G. Don. Plant Sci. 171, 271276.

    • Search Google Scholar
    • Export Citation
  • 23.

    Kishorekumar, A., Jaleel, C. A., Manivannan, P., Sankar, B., Sridharan, R. et al. (2006) Differential effects of hexaconazole and paclobutrazol on the foliage characteristics of Chinese potato (Solenostemon rotundifolius Poir., J. K. Morton). Acta Biol. Szegediensis 50, 127129.

    • Search Google Scholar
    • Export Citation
  • 24.

    Kumar, P. A., Lakshmikumaran, M., Abrol, Y. P. (1993) Hormonal regulation of nitrate reductase gene expression in Hordeum vulgare. Indian J. Expt. Biol. 31, 472473.

    • Search Google Scholar
    • Export Citation
  • 25.

    Lee, S. H., Lee, D. G., Woo, H. S., Lee, K. W., Kim, D. H. (2006) Production of transgenic orchardgrass via Agrobacterium-mediated transformation of seed-derived callus tissues. Plant Sci. 171, 408414.

    • Search Google Scholar
    • Export Citation
  • 26.

    Lowry, O. H., Rosenbrough, N. J., Randall, R. J. (1951) Protein measurement with the Folin-phenol reagent. J. Biol. Chem. 183, 265275.

    • Search Google Scholar
    • Export Citation
  • 27.

    Mérigout, P., Lelandais, M., Bitton, F. et al. (2008) Physiological and transcriptomic aspects of urea uptake and assimilation in Arabidopsis plants. Plant Physiol. 147, 12251238.

    • Search Google Scholar
    • Export Citation
  • 28.

    Montfort, F., Klepper, B. L., Smiley, R. W. (1996) Effects of two triazole seed-treatments, triticonazole and triadiminol, on growth and development of wheat. Pest. Sci. 46, 315322.

    • Search Google Scholar
    • Export Citation
  • 29.

    Oaks, A. (1994) Efficiency of nitrogen utilization in C3 and C4 cereals. Plant Physiol. 106, 407414.

  • 30.

    Polacco, J. C., Holland, M. A. (1993) Roles of urease in plant cells. In: Int. Rev. Cyt. – A Survey of Cell Biol. 145, 65103.

  • 31.

    Premabatidevi, R. K. (1998) Effect of IAA, GA3 and kinetin on nitrate reductase and nitrite reductase in the leaves of a tree legume (Perkia javanika Merr). Indian J. Plant Physiol. 3, 97101.

    • Search Google Scholar
    • Export Citation
  • 32.

    Rahayu, Y. S., Walch-Liu, P., Neumann, G., von Wiren, N., Bangerth, F. (2005) Root-derived cytokinins as long-distance signals for NO3 – induced stimulation of leaf growth. J. Exp. Bot. 56, 11431152.

    • Search Google Scholar
    • Export Citation
  • 33.

    Rajagopalan, L. E., Malter, J. S. (1996) Turnover and translation of in vitro synthesized messenger RNAs in transfected, normal cells. J. Biol. Chem. 271, 1987119876.

    • Search Google Scholar
    • Export Citation
  • 34.

    Renaut, J., Hausman, J. F., Wisniewski, M. E. (2006) Proteomics and low temperature studies: bridging the gap between gene expression and metabolism. Physiol. Plant. 126, 97109.

    • Search Google Scholar
    • Export Citation
  • 35.

    Sahulka, J., Gaudinova, A. (1975) Regulation on glutamate dehydrogenase level in excised pea roots by some exogenously supplied compounds with auxin activity. Biol. Plant. 17, 228230.

    • Search Google Scholar
    • Export Citation
  • 36.

    Satvir, K., Gupta, A. K., Narinder, K. (2003) Priming of chickpea seeds with water and mannitol overcomes the effect of salt stress on seedling growth. ICPN 10, 1820.

    • Search Google Scholar
    • Export Citation
  • 37.

    Schmitt, J. M., Piepenbrock, M. (1992) Regulation of phosphoenolpyruvate carboxylase and crassulacean acid metabolism induction in Mesembryanthemum cystallinum L. by cytokinin modulation of leaf gene expression by roots. Plant Physiol. 99, 16641669.

    • Search Google Scholar
    • Export Citation
  • 38.

    Setia, R. C., Narang, S. (1985) Effects of salinity stress and plant growth regulators on seed germination and seedling growth in pea (Pisum sativum). Flora (Jena) 177, 369375.

    • Search Google Scholar
    • Export Citation
  • 39.

    Shang, Z. (2000) Effect of 6-BA and KT on photophosphorylation activity in wheat flag leaves under water stress. Acta Agriculturae Boreali-Sinica 15, 3438.

    • Search Google Scholar
    • Export Citation
  • 40.

    Sirko, A., Brodzik, R. (2000) Plant ureases: roles and regulation. Acta Biochim. Pol. 47, 11891195.

  • 41.

    Sugiharto, B., Burnell, J. N., Sugiyama, T. (1992) Cytokinin is required to induce the nitrogendependent accumulation of mRNAs for phosphoenolpyruvate carboxylase and carbonic anhydrase in detached maize leaves. Plant Physiol. 100, 153156.

    • Search Google Scholar
    • Export Citation
  • 42.

    Thomas, J. C., McElwain, E. F., Bohnert, H. J. (1992) Convergent induction of osmotic stressresponses. Abscisic acid, cytokinin, and effects of NaCl. Plant Physiol. 100, 416423.

    • Search Google Scholar
    • Export Citation
  • 43.

    Vuylsterker, C., Leleu, O., Rambour, S. (1997) Influence of BAP and NAA on the expression of nitrate reductase in excised chicory roots. J. Expt. Bot. 48, 10791085.

    • Search Google Scholar
    • Export Citation
  • 44.

    Wingler, A., von Schaewen, A., Leegood, R. C., Lea, P. J., Quick, W. P. (1998) Regulation of leaf senescence by cytokinin, sugars, and light. Effects on NADH-dependent hydroxypyruvate reductase. Plant Physiol. 116, 329335.

    • Search Google Scholar
    • Export Citation
  • 45.

    Xia, X. J., Wang, Y. J., Zhou, Y. H., Tao, Y., Mao, W. H. et al. (2009) Reactive oxygen species are involved in brassinosteroid-induced stress tolerance in cucumber. Plant Physiol. 150, 801814.

    • Search Google Scholar
    • Export Citation
  • 46.

    Yadav, U. P., Ivakov, A., Feill, R., Duan, G. Y., Walther, D. (2014) The sucrose–trehalose 6-phosphate (Tre6P) nexus: specificity and mechanisms of sucrose signaling by Tre6P. J. Exp. Bot. doi: 10.1093/jxb/ert457.

    • Search Google Scholar
    • Export Citation
  • 47.

    Zhang, Y. H., Wang, Z. M., Huang, Q., Shu, W. (2008) Phosphoenolpyruvate carboxylase activity in ear organs is related to protein concentration in grains of winter wheat. J. Cereal Sci. 47, 386391.

    • Search Google Scholar
    • Export Citation
  • 48.

    Zonia, L. E., Stebbins, N. E., Polacco, J. C. (1995) Essential role of urease in germination of nitrogenlimited Arabidopsis thaliana seeds. Plant Physiol. 107, 10971103.

    • Search Google Scholar
    • Export Citation