Abstract
The expression profiles of three Brassica rapa metallothionein genes (BrMT 1–3) were determined in 7-day-old seedlings exposed to various exogenous factors including plant hormones, heavy metals and abiotic stresses. BrMT1, BrMT2, and BrMT3 were representatives of MT gene type 1, type 2, and type 3, respectively, according to their cysteine alignment. BrMT2 showed a relatively higher basal expression level compared to BrMT1 and BrMT3 under normal conditions. The BrMT1 transcript was markedly increased by various factors including ethephon, polyethylene glycol and hydrogen peroxide, with no down-regulation evident. On the contrary, BrMT2 expression was down-regulated by abscisic acid, salicylic acid, and methyl jasmonate. Heavy metals did not increase BrMT2 expression. BrMT3 expression was only marginally and non-significantly up- and down-regulated by the stress conditions tested. Promoter regions of BrMT1 and BrMT2 display different cis-acting elements supporting the different responses of both genes against various stresses. The results demonstrate the differential regulation of BrMT1–3 by various plant exogenous factors, and indicate the utility of the BrMT1 promoter as a multiple stress inducible promoter.
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Abbreviations
- Br:
-
Brassica rapa
- MT:
-
Metallothionein
- PC:
-
Phytochelatins
- PEG:
-
Polyethylene glycol
- ROS:
-
Reactive oxygen species
- SA:
-
Salicylic acid
- ABA:
-
Abscisic acid
- MeJA:
-
Methyl jasmonate
- ET:
-
Ethephon
- H2O2 :
-
Hydrogen peroxide
- UBQ:
-
Ubiquitin
References
MacFarlane GR (2002) Leaf biochemical parameters in Avicennia marina (Forsk.) Vierh as potential biomarkers of heavy metal stress in estuarine ecosystems. Mar Pollut Bull 44(3):244–256
Ebbs S, Uchil S (2008) Cadmium and zinc induced chlorosis in Indian mustard [Brassica juncea (L.) Czern] involves preferential loss of chlorophyll b. Photosynthetica 46(1):49–55
Lingua G, Franchin C, Todeschini V, Castiglione S, Biondi S, Burlando B, Parravicini V, Torrigiani P, Berta G (2008) Arbuscular mycorrhizal fungi differentially affect the response to high zinc concentrations of two registered poplar clones. Environ Pollut 153(1):137–147
Robinson NJ, Tommey AM, Kuske C, Jackson PJ (1993) Plant metallothioneins. Biochem J 295(Pt 1):1–10
Zenk MH (1996) Heavy metal detoxification in higher plants-a review. Gene 179(1):21–30
Hamer DH (1986) Metallothionein. Annu Rev Biochem 55:913–951
Kaegi JHR, Schaeffer A (1988) Biochemistry of metallothionein. Biochemistry 27(23):8509–8515
Cobbett C, Goldsbrough P (2002) Phytochelatins and metallothioneins: roles in heavy metal detoxification and homeostasis. Annu Rev Plant Biol 53:159–182
Margoshes M, Vallee BL (1957) A cadmium protein from equine kidney cortex. J Am Chem Soc 79(17):4813–4814
Zhigang A, Cuijie L, Yuangang Z, Yejie D, Wachter A, Gromes R, Rausch T (2006) Expression of BjMT2, a metallothionein 2 from Brassica juncea, increases copper and cadmium tolerance in Escherichia coli and Arabidopsis thaliana, but inhibits root elongation in Arabidopsis thaliana seedlings. J Exp Bot 57(14):3575–3582
Chen HJ, Hou WC, Yang CY, Huang DJ, Liu JS, Lin YH (2003) Molecular cloning of two metallothionein-like protein genes with differential expression patterns from sweet potato (Ipomoea batatas) leaves. J Plant Physiol 160(5):547–555
Xue T, Li X, Zhu W, Wu C, Yang G, Zheng C (2009) Cotton metallothionein GhMT3a, a reactive oxygen species scavenger, increased tolerance against abiotic stress in transgenic tobacco and yeast. J Exp Bot 60(1):339–349
Kumar PBAN, Dushenkov V, Motto H, Raskin I (1995) Phytoextraction: the use of plants to remove heavy metals from soils. Environ Sci Technol 29(5):1232–1238
Salt DE, Blaylock M, Kumar NPBA, Dushenkov V, Ensley BD, Chet I, Raskin I (1995) Phytoremediation: a novel strategy for the removal of toxic metals from the environment using plants. Nat Biotech 13(5):468–474
Blaylock MJ, Salt DE, Dushenkov S, Zakharova O, Gussman C, Kapulnik Y, Ensley BD, Raskin I (1997) Enhanced accumulation of Pb in indian mustard by soil-applied chelating agents. Environ Sci Technol 31(3):860–865
Kim SH, Lee H, Song W, Choi K, Hur Y (2007) Chloroplast-targeted BrMT1 (Brassica rapa type-1 metallothionein) enhances resistance to cadmium and ROS in transgenic arabidopsis plants. J Plant Biol 50(1):1–7
Gisbert C, Clemente R, Navarro-Aviñó J, Baixauli C, Ginér A, Serrano R, Walker D, Bernal M (2006) Tolerance and accumulation of heavy metals by Brassicaceae species grown in contaminated soils from Mediterranean regions of Spain. Environ Exp Bot 56(1):19–27
Ishikawa S, Ae N, Murakami M, Wagatsuma T (2006) Is Brassica juncea a suitable plant for phytoremediation of cadmium in soils with moderately low cadmium contamination?—Possibility of using other plant species for Cd-phytoextraction. Soil Sci Plant Nutr 52(1):32–42
Murashige T, Skoog F (1962) A revised medium for rapid growth and bio assays with tobacco tissue cultures. Physiol Plant 15(3):473–497
Yang Z, Wu Y, Li Y, Ling HQ, Chu C (2009) OsMT1a, a type 1 metallothionein, plays the pivotal role in zinc homeostasis and drought tolerance in rice. Plant Mol Biol 70(1–2):219–229
Yuan J, Chen D, Ren Y, Zhang X, Zhao J (2008) Characteristic and expression analysis of a metallothionein gene, OsMT2b, down-regulated by cytokinin suggests functions in root development and seed embryo germination of rice. Plant Physiol 146(4):1637–1650
Huang G-Y, Wang Y-S (2009) Expression analysis of type 2 metallothionein gene in mangrove species (Bruguiera gymnorrhiza) under heavy metal stress. Chemosphere 77(7):1026–1029
Bratic AM, Majic DB, Samardzic JT, Maksimovic VR (2009) Functional analysis of the buckwheat metallothionein promoter: tissue specificity pattern and up-regulation under complex stress stimuli. J Plant Physiol 166(9):996–1000
Fukuzawa H, Yu LH, Umeda-Hara C, Tagawa M, Uchimiya H (2004) The rice metallothionein gene promoter does not direct foreign gene expression in seed endosperm. Plant Cell Rep 23(4):231–235
Ahmadi N, Dellerme S, Laplaze L, Guermache F, Auguy F, Duhoux E, Bogusz D, Guiderdoni E, Franche C (2003) The promoter of a metallothionein-like gene from the tropical tree casuarina glauca is active in both annual dicotyledonous and monocotyledonous plants. Transgenic Res 12(3):271–281
Guo W-J, Bundithya W, Goldsbrough PB (2003) Characterization of the Arabidopsis metallothionein gene family: tissue-specific expression and induction during senescence and in response to copper. New Phytol 159(2):369–381
Lü S, Gu H, Yuan X, Wang X, Wu A-M, Qu L, Liu J-Y (2007) The GUS reporter-aided analysis of the promoter activities of a rice metallothionein gene reveals different regulatory regions responsible for tissue-specific and inducible expression in transgenic Arabidopsis. Transgenic Res 16(2):177–191
Navabpour S, Morris K, Allen R, Harrison E, A-H-Mackerness S, Buchanan-Wollaston V (2003) Expression of senescence-enhanced genes in response to oxidative stress. J Exp Bot 54(391):2285–2292
Butt A, Mousley C, Morris K, Beynon J, Can C, Holub E, Greenberg JT, Buchanan-Wollaston V (1998) Differential expression of a senescence-enhanced metallothionein gene in Arabidopsis in response to isolates of Peronospora parasitica and Pseudomonas syringae. Plant J 16(2):209–221
Chatthai M, Osusky M, Osuska L, Yevtushenko D, Misra S (2004) Functional analysis of a Douglas-fir metallothionein-like gene promoter: transient assays in zygotic and somatic embryos and stable transformation in transgenic tobacco. Planta 220(1):118–128
Ramli Z, Abdullah S (2010) Functional characterisation of the oil palm type 3 metallothionein-like gene (MT3-B) promoter. Plant Mol Biol Report 28(3):531–541
Omidvar V, Abdullah S, Izadfard A, Ho C, Mahmood M (2010) The oil palm metallothionein promoter contains a novel AGTTAGG motif conferring its fruit-specific expression and is inducible by abiotic factors. Planta 232(4):925–936
Acknowledgments
This work was supported by the KRIBB initiative program and grant from Cabbage Genomics Assisted Breeding Supporting Research Center funded to H. Kim by Ministry for Food, Agriculture, Forestry and Fisheries, Korea.
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Ahn, Y.O., Kim, S.H., Lee, J. et al. Three Brassica rapa metallothionein genes are differentially regulated under various stress conditions. Mol Biol Rep 39, 2059–2067 (2012). https://doi.org/10.1007/s11033-011-0953-5
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DOI: https://doi.org/10.1007/s11033-011-0953-5