Abstract
Sinapine is the most prominent antinutritive compound in the seeds of oilseed rape (Brassica napus L.). A reduction in sinapine content could improve the quality of rapeseed meal as an animal feed and in food industry. We had selected loss-of-function mutations of two sinapine biosynthesis genes BnSGT and BnREF1 and crossed them to produce double mutants. We measured their expression and enzyme activities in developing seeds as well as sinapoyl ester accumulation in mature seeds in three segregating F2 populations. Significant depletion of SGT enzyme activity in developing seeds proved loss of function of both gene copies and ruled out background effects. REF1 enzyme activities showed minor reductions and pointed at different substrate specificities of the paralogs and the presence of unspecific aldehyde dehydrogenases. Sinapine contents in the double mutants dropped dramatically by up to 71 %. F3 seeds with two stop-codon mutations in BnREF1 genes had the lowest sinapine contents (2.4 mg/g) as compared to the EMS control (7.5 mg/g). A BnREF1 splice site mutation did not result in a decrease in seed sinapine content probably due to incomplete splicing. We demonstrate that only the combination of different knockdown mutations drastically alters the composition of a major secondary metabolite. The results cast new light on the activities of gene paralogs in a polyploid species. The selected double mutants will be of major importance to further improve the quality of rapeseed.
Similar content being viewed by others
References
Allender CJ, King GJ (2010) Origins of the amphiploid species Brassica napus L. investigated by chloroplast and nuclear molecular markers. BMC Plant Biol 10:54
Baumert A, Milkowski C, Schmidt J, Nimtz M, Wray V, Strack D (2005) Formation of a complex pattern of sinapate esters in Brassica napus seeds, catalyzed by enzymes of a serine carboxypeptidase-like acyltransferase family? Phytochemistry 66:1334–1345
Bhinu VS, Schäfer U, Li R, Huang J, Hannoufa A (2009) Targeted modulation of sinapine biosynthesis pathway for seed quality improvement in Brassica napus. Transgenic Res 18:31–44
Blanc G, Wolfe KH (2004) Functional divergence of duplicated genes formed by polyploidy during Arabidopsis evolution. Plant Cell 16:1679–1691
Chang YF, Imam JS, Wilkinson ME (2007) The nonsense-mediated decay RNA surveillance pathway. Annu Rev Biochem 76:51–74
Clauß K, von Roepenack-Lahaye E, Böttcher C, Roth MR, Welti R, Erban A, Kopka J, Scheel D, Milkowski C, Strack D (2011) Overexpression of sinapine esterase BnSCE3 in oilseed rape seeds triggers global changes in seed metabolism. Plant Physiol 155:1127–1145
Dixon RA, Achnine L, Kota P, Liu CJ, Reddy MSS, Wang LJ (2002) The phenylpropanoid pathway and plant defence: a genomics perspective. Mol Plant Pathol 3:371–390
Gadjieva R, Axelsson E, Olsson U, Vallon-Christersson J, Hansson M (2004) Nonsense-mediated mRNA decay in barley mutants allows the cloning of mutated genes by a microarray approach. Plant Physiol Biochem 42:681–685
Harloff HJ, Wegmann K (1993) Evidence for a mannitol cycle in Orobanche ramosa and Orobanche crenata. J Plant Physiol 141:513–520
Harloff HJ, Lemcke S, Mittasch J, Frolov A, Wu JG, Dreyer F, Leckband G, Jung C (2012) A mutation screening platform for rapeseed (Brassica napus L.) and the detection of sinapine biosynthesis mutants. Theor Appl Genet 124:957–969
Hughes J, Hughes MA (1994) Multiple secondary plant product UDP-glucose glucosyltransferase genes expressed in cassava (Manihot esculenta Crantz) cotyledons. Mitochondr DNA 5:41–49
Hüsken A, Baumert A, Strack D, Becker HC, Möllers C, Milkowski C (2005) Reduction of sinapate ester content in transgenic oilseed rape (Brassica napus) by dsRNAi-based suppression of BnSGT1 gene expression. Mol Breed 16:127–138
Isshiki M, Morino K, Nakajima M, Okagaki RJ, Wessler SR, Izawa T, Shimamoto K (1998) A naturally occurring functional allele of the rice waxy locus has a GT to TT mutation at the 5′ splice site of the first intron. Plant J 15:133–138
Isshiki M, Yamamoto Y, Satoh H, Shimamoto K (2001) Nonsense-mediated decay of mutant waxy mRNA in rice. Plant Physiol 125:1388–1395
Jofuku KD, Schipper RD, Goldberg RB (1989) A frameshift mutation prevents Kunitz trypsin inhibitor mRNA accumulation in soybean embryos. Plant Cell 1:427–435
Jordan T, Schornack S, Lahaye T (2002) Alternative splicing of transcripts encoding Toll-like plant resistance proteins—what’s the functional relevance to innate immunity? Trends Plant Sci 7:392–398
Kusumi J, Iba K (1998) Characterization of a nonsense mutation in FAD7, the gene which encodes ω-3 desaturase in Arabidopsis thaliana. J Plant Res 111:87–91
Livak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the \( 2^{{ - \Delta \Delta C_{\text{t}} }} \) method. Methods 25:402–408
Macknight R, Duroux M, Laurie R, Dijkwel P, Simpson G, Dean C (2002) Functional significance of the alternative transcript processing of the Arabidopsis floral promoter FCA. Plant Cell 14:877–888
Maple J, Møller S (2007) Mutagenesis in Arabidopsis. In: Rosato E (ed) Methods in molecular biology, vol 362., Circadian rhythmsHumana Press, Totowa, pp 197–206
Marchitti SA, Brocker C, Stagos D, Vasiliou V (2008) Non-P450 aldehyde oxidizing enzymes: the aldehyde dehydrogenase superfamily. Expert Opin Drug Met 4:697–720
McCallum CM, Comai L, Greene EA, Henikoff S (2000) Targeting induced local lesions in genomes (TILLING) for plant functional genomics. Plant Physiol 123:439–442
Milkowski C, Baumert A, Schmidt D, Nehlin L, Strack D (2004) Molecular regulation of sinapate ester metabolism in Brassica napus: expression of genes, properties of the encoded proteins and correlation of enzyme activities with metabolite accumulation. Plant J 38:80–92
Mittasch J, Mikolajewski S, Breuer F, Strack D, Milkowski C (2010) Genomic microstructure and differential expression of the genes encoding UDP-glucose:sinapate glucosyltransferase (UGT84A9) in oilseed rape (Brassica napus). Theor Appl Genet 120:1485–1500
Mittasch J, Böttcher C, Frolov A, Strack D, Milkowski C (2013) Reprogramming the phenylpropanoid metabolism in seeds of Brassica napus by suppressing the orthologs of REDUCED EPIDERMAL FLUORESCENCE1. Plant Physiol 161:1656–1669
Nagaharu U (1935) Genome-analysis in Brassica with special reference to the experimental formation of B. napus and its peculiar mode of fertilization. Jpn J Bot 7:369–452
Nagel F, Slawski H, Adem H, Tressel RP, Wysujack K, Schulz C (2012) Albumin and globulin rapeseed protein fractions as fish meal alternative in diets fed to rainbow trout (Oncorhynchus mykiss W.). Aquaculture 354:121–127
Nair RB, Joy RWI, Kurylo E, Shi X, Schnaider J, Datla RSS, Keller WA, Selvaraj G (2000) Identification of a CYP84 family of cytochrome P450-dependent mono-oxygenase genes in Brassica napus and perturbation of their expression for engineering sinapine reduction in the seeds. Plant Physiol 123:1623–1634
Nair RB, Bastress KL, Ruegger MO, Denault JW, Chapple C (2004) The Arabidopsis thaliana REDUCED EPIDERMAL FLUORESCENCE1 gene encodes an aldehyde dehydrogenase involved in ferulic acid and sinapic acid biosynthesis. Plant Cell 16:544–554
Quesada V, Macknight R, Dean C, Simpson GG (2003) Autoregulation of FCA pre-mRNA processing controls Arabidopsis flowering time. Sci Signal 22:3142
Saito M, Nakamura T (2005) Two point mutations identified in emmer wheat generate null Wx-A1 alleles. Theor Appl Genet 110:276–282
Schranz ME, Lysak MA, Mitchell-Olds T (2006) The ABC’s of comparative genomics in the Brassicaceae: building blocks of crucifer genomes. Trends Plant Sci 11:535–542
Shahidi F, Naczk M (1992) An overview of the phenolics of canola and rapeseed: chemical, sensory and nutritional significance. J Am Oil Chem Soc 69:917–924
Stephenson P, Baker D, Girin T, Perez A, Amoah S, King GJ, Ostergaard L (2010) A rich TILLING resource for studying gene function in Brassica rapa. BMC Plant Biol 10:62
van Hoof A, Green PJ (2006) NMD in plants. In: Maquat L (ed) Nonsense-mediated mRNA decay. Landes Biosci, New York, pp 167–172
Veitia RA (2004) Gene dosage balance in cellular circuits and pathways: implications for dominance and gene duplicability. Genetics 168:569–574
Voelker TA, Staswick P, Chrispeels MJ (1986) Molecular analysis of two phytohemagglutinin genes and their expression in Phaseolus vulgaris cv. Pinto, a lectin-deficient cultivar of the bean. EMBO J 5:3075
Voelker TA, Moreno J, Chrispeels MJ (1990) Expression analysis of a pseudogene in transgenic tobacco: a frameshift mutation prevents mRNA accumulation. Plant Cell 2:255–261
Wang JLY, Wu B, Liu J, Jiang C, Shi L, Zhao J, King G, Meng J (2009) The evolution of Brassica napus FLOWERING LOCUS T paralogues in the context of inverted chromosomal duplication blocks. BMC Evol Biol 9:271
Wolfram K, Schmidt J, Wray V, Milkowski C, Schliemann W, Strack D (2010) Profiling of phenylpropanoids in transgenic low-sinapine oilseed rape (Brassica napus). Phytochemistry 71:1076–1084
Zhang XC, Gassmann W (2003) RPS4-mediated disease resistance requires the combined presence of RPS4 transcripts with full-length and truncated open reading frames. Plant Cell 15:2333–2342
Zum Felde T, Baumert A, Strack D, Becker HC, Moellers C (2007) Genetic variation for sinapate ester content in winter rapeseed (Brassica napus L.) and development of NIRS calibration equations. Plant Breeding 126:291–296
Acknowledgments
We thank Gislind Bräcker and Monika Bruisch for technical assistance in the laboratory and in the greenhouse, and Prof. Dr. Wolfgang Bilger and Jens Hermann from the Institute of Botany, University of Kiel for performing HPLC analyses. We thank the Zentrum für Molekulare Biowissenschaften (ZBM), University of Kiel for providing the facilities for DNA isolation and normalization. We are also grateful to the Institute for Clinical Molecular Biology, University Kiel for Sanger sequencing. This project was funded by the seed companies Norddeutsche Pflanzenzucht Hans-Georg Lembke KG (Hohenlieth, Germany), Deutsche Saatveredelung AG (Lippstadt, Germany), KWS SAAT AG (Einbeck, Germany), the German Federal Ministry for Education, Research and Technology BMBF (GABI Future Grant No. 0315052C), and the German Research foundation (DFG) Grant No. Ju205/14-1.
Author information
Authors and Affiliations
Corresponding author
Additional information
Nazgol Emrani and Hans-Joachim Harloff have contributed equally to this work.
Accession numbers: BnaA.SGT.a (FM872285), BnaC.SGT.a (FM872284), BnaC.REF1.a (FN995990), and BnaA.REF1.a (FN995991).
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Emrani, N., Harloff, HJ., Gudi, O. et al. Reduction in sinapine content in rapeseed (Brassica napus L.) by induced mutations in sinapine biosynthesis genes. Mol Breeding 35, 37 (2015). https://doi.org/10.1007/s11032-015-0236-2
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11032-015-0236-2