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Identification and characterization of finger millet OPAQUE2 transcription factor gene under different nitrogen inputs for understanding their role during accumulation of prolamin seed storage protein

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Abstract

In this study, we report the isolation and characterization of the mRNA encoding OPAQUE2 (O2) like TF of finger millet (FM) (Eleusine coracana) (EcO2). Full-length EcO2 mRNA was isolated using conserved primers designed by aligning O2 mRNAs of different cereals followed by 3′ and 5′ RACE (Rapid Amplification of cDNA Ends). The assembled full-length EcO2 mRNA was found to contain an ORF of 1248-nt coding the 416 amino acids O2 protein. Domain analysis revealed the presence of the BLZ and bZIP-C domains which is a characteristic feature of O2 proteins. Phylogenetic analysis of EcO2 protein with other bZIP proteins identified using finger millet transcriptome data and O2 proteins of other cereals showed that EcO2 shared high sequence similarity with barley BLZ1 protein. Transcripts of EcO2 were detected in root, stem, leaves, and seed development stages. Furthermore, to investigate nitrogen responsiveness and the role of EcO2 in regulating seed storage protein gene expression, the expression profiles of EcO2 along with an α-prolamin gene were studied during the seed development stages of two FM genotypes (GE-3885 and GE-1437) differing in grain protein content (13.8 and 6.2%, respectively) grown under increasing nitrogen inputs. Compared to GE-1437, the EcO2 was relatively highly expressed during the S2 stage of seed development which further increased as nitrogen input was increased. The Ecα-prolamin gene was strongly induced in the high protein genotype (GE-3885) at all nitrogen inputs. These results indicate the presence of nitrogen responsiveness regulatory elements which might play an important role in accumulating protein in FM genotypes through modulating EcO2 expression by sensing plant nitrogen status.

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Abbreviations

DAS:

Day after sowing

HPG:

High protein genotype,

LPG:

Low protein genotype

N:

Nitrogen

NUE:

Nitrogen use efficiency

O2:

Opaque2

PBF:

Prolamine-binding factor

qPCR:

Real-time PCR

RACE:

Rapid amplification of cDNA ends

SSP:

Seed storage proteins

UTR:

Untranslated region

References

  • Albani D, Hammond-Kosack MC, Smith C, Conlan S, Colot V, Holdsworth M, Bevan MW (1997) The wheat transcriptional activator SPA a seed-specific bZIP protein that recognizes the GCN4 like motif in the bifactorial endosperm box of prolamin genes. Plant Cell 9:171–184

    Article  CAS  Google Scholar 

  • Bailey TL, Williams N, Misleh C, Li WW (2006) MEME discovering and analyzing DNA and protein sequence motifs. Nucleic Acids Res 34:W369–W373

    Article  CAS  Google Scholar 

  • Balconi C (1993) The accumulation of zein polypeptide and zein mRNA in cultured endosperms of maize is modulated by nitrogen supply. Plant J 3:325–334

    Article  CAS  Google Scholar 

  • Blom N (1999) Sequence and structure-based prediction of eukaryotic protein phosphorylation sites. J Mol Biol 294:1351–1362

    Article  CAS  Google Scholar 

  • Ciceri P, Gianazza E, Lazzari B, Lippoli G, Genga A, Hoschek G, Schmidt RJ, Viotti A (1997) Phosphorylation of Opaque-2 changes diurnally and impacts its DNA binding activity. Plant Cell 9:97–108

    Article  CAS  Google Scholar 

  • Fakrudin B, Shashidhar HE, Kulkarni RS, Hittalmani S (2004) Genetic diversity assessment of finger millet (Eleusine coracana, Gaertn) germplasm through RAPD analysis. PGR Newslett 138:50–54

    Google Scholar 

  • Gowda J, Haider ZA, Gupta A, Venkateshwara T, Mahadevaiah C, Somu G, Seetharam A (2005) Finger millet [Eleusine coracana(L.) Gaertn] Core germplasm for utilization in crop improvement. Published by the All India Coordinated Small Millet Improvement Project ICAR University of Agricultural Sciences Bangalore India, 171

  • Gupta N, Gupta AK, Singh NK, Kumar A (2011) Differential expression of PBF Dof transcription factor in different tissues of three finger millet genotypes differing in seed protein content and color. J Plant Mol Biol Rep 29:69–76

    Article  CAS  Google Scholar 

  • Hammond Kosack MC, Holdsworth MJ, Bevan MW (1993) In vivo foot printing of a low molecular weight glutenin gene (LMWG-1D1) in wheat endosperm. EMBO J 12:545–554

    CAS  Google Scholar 

  • Hartings H, Maddaloni M, Lazzaroni N, Fonzo ND, Motto M, Salamini F, Thompson R (1989) The O2 gene which regulates zein deposition in maize endosperm encodes a protein with structural homologies to transcriptional activators. EMBO J 8:2795–2801

    CAS  Google Scholar 

  • Hurst HC (1995) Transcription factors 1 bZIP proteins. Protein Profile 2:101–168

    CAS  Google Scholar 

  • Kreis M, Forde BG, Rahman S, Miflin BJ, Shewry PR (1985) Molecular evolution of the seed storage proteins of barley, rye and wheat. J Mol Biol 183:499–502

    Article  CAS  Google Scholar 

  • Kumar R, Taware R, Gaur VS, Guru SK, Kumar A (2009) Influence of nitrogen on the expression of TaDof1 transcription factor in wheat and its relationship with photo synthetic and ammonium assimilating efficiency. Mol Biol Rep. https://doi.org/10.1007/s11033-008-9436-8

    Google Scholar 

  • Kumar A, Gaur VS, Goel A, Gupta AK (2014) De Novo Assembly and characterization of developing spikes transcriptome of finger millet (Eleusine coracana): a minor crop Having Nutraceutical Properties. Plant Mol Biol Rep 1:18

    Google Scholar 

  • Kumar A, Metwal M, Kaur S, Gupta AK, Puranik S, Singh S, Singh M, Gupta S, Babu BK, Sood S, Yadav R (2016) Nutraceutical value of Finger Millet [Eleusine coracana (L.) Gaertn] and their improvement using omics approaches. Front Plant Sci 7:934

    Google Scholar 

  • Livak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta DeltaC (T)) method. Methods 25:402–408

    Article  CAS  Google Scholar 

  • Marzábal P, Gas E, Fontanet P, Vicente-Carbajosa J, Torrent M, Ludevid MD (2008) The maize Dof protein PBF activates transcription of gamma-zein during maize seed development. Plant Mol Biol 67:41–54

    Article  Google Scholar 

  • Mena M, Vicente CJ, Schmidt RJ, Carbonero P (1998) An endosperm specific DOF protein from barley, highly conserved in wheat, binds to and activates transcription from the prolamin box of a native B-hordein promoter in barley endosperm. Plant J 16:53–62

    Article  CAS  Google Scholar 

  • Mirza N, Sharma N, Srivastava S, Kumar A (2015) Variation in popping quality related to physical, biochemical and nutritional properties of finger millet genotypes. In: Proceedings of the National Academy of Sciences, India section B: biological sciences, vol 85, no 2. pp 507–515

  • Muller M, Knudsen S (1993) The nitrogen response of a barley C-hordein promoter is controlled by positive and negative regulation of the GCN4 and endosperm box. Plant J 4:343–355

    Article  CAS  Google Scholar 

  • Murphy DJ (2000) Shewry PR, Casey R, eds. 1999. Seed proteins. 883 pp. Dordrecht: Kluwer. £315 (hardback). Ann Bot 86(2):434–435. https://doi.org/10.1006/anbo.2000.1212

    Article  Google Scholar 

  • Nakase M, Aoki N, Matsuda T, Adachi T (1997) Characterization of a novel rice bZIP protein which binds to the alpha-globulin promoter. Plant Mol Biol 33:513–522

    Article  CAS  Google Scholar 

  • Onate L, Vicente CJ, Lara P, Diaz I, Carbonero P (1999) Barley BLZ2 a seed-specific bZIP protein that interacts with BLZ1 in vivo and activates transcription from the GCN4 like motif of B-hordein promoters in barley endosperm. J Biol Chem 274:9175–9182

    Article  CAS  Google Scholar 

  • Onodera Y, Suzuki A, Wu CY, Washida H, Takaiwa F (2001) A rice functional transcriptional activator RISBZ1 responsible for endosperm specific expression of storage protein genes through GCN4 motif. J Biol Chem 276:14139–14152

    Article  CAS  Google Scholar 

  • Osborne TB (ed) (1924) The Vegetable proteins (monographs on biochemistry), 2nd edn. Longmans, Green and Co, London, p 154

    Google Scholar 

  • Pietro C et al (1999) The maize O2 and PBF proteins act additively to promote transcription from storage protein gene promoters in rice endosperm cells. Plant Cell Physiol 45:1509–1518

    Google Scholar 

  • Shewry PR, Tatham AS (1999) The characteristics, structures and evolutionary relationships of prolamins. In: Shewry PR, Casey R (eds) ‘‘Seed Proteins’’, pp. 11–36. Kluwer Academic Publishers, Dordrecht, The Netherlands

  • Tamura K, Dudley J, Nei M, Kumar S (2007) MEGA4 molecular evolutionary genetics analysis (MEGA) software version 4.0. Mol Biol Evol 24:1596–1599

    Article  CAS  Google Scholar 

  • Vicente CJ, Onate L, Lara P, Diaz I, Carbonero P (1998) Barley BLZ1 a bZIP transcriptional activator that interacts with endosperm specific gene promoters. Plant J 13:629–640

    Article  Google Scholar 

  • Vicente-Carbajosa J, Moose SP, Parsons RL, Schmidt RJ (1997) A maize zinc-finger protein binds the prolamin box in zein gene promoters and interacts with the basic leucine zipper transcriptional activator Opaque2. Proc Natl Acad Sci USA 94:7685–7690

    Article  CAS  Google Scholar 

  • Wu CY, Adachi T, Hatano T, Washida H, Suzuki A, Takaiwa F (1998) Promoters of rice seed storage protein genes direct endosperm-specific gene expression in transgenic rice. Plant Cell Physiol 39:885–889

    Article  CAS  Google Scholar 

  • Yamamoto MP, Onodera Y, Touno SM, Takaiwa F (2006) Synergism between RPBF Dof and RISBZ1 bZIP activators in the regulation of rice seed expression genes. Plant Physiol 141:1694–1707

    Article  CAS  Google Scholar 

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Acknowledgements

This work was supported by Science and Engineering Research Board (SERB), DST, New Delhi, India, in the form of “Fast Track Scheme for Young Scientist” awarded to VSG and SG (SR/FT/LS-33/2011 and YSS/2015/00536). The logistic support provided by the Director, Experiment Station, G.B. Pant University of Agriculture and Technology, Pantnagar is also thankfully acknowledged.

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AK conceived the idea and conceptualized and designed the manuscript. VSG and LK are involved in the lab work of the presented R & D data. VSG, LK, and SG wrote the manuscript. JPJ, DP, and AK contributed in critically revising the draft and updating the manuscript for publication.

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Correspondence to Anil Kumar.

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Gaur, V.S., Kumar, L., Gupta, S. et al. Identification and characterization of finger millet OPAQUE2 transcription factor gene under different nitrogen inputs for understanding their role during accumulation of prolamin seed storage protein. 3 Biotech 8, 163 (2018). https://doi.org/10.1007/s13205-018-1150-1

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