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ABSTRACT: The expression ofArabidopsis PDF1.2 gene is regulated by jasmonic acid (JA) and ethylene (ET). It also has been well documented that GCC box is an element responsive
to ET, however, the responsive mechanism of JA in such plant defense gene expression is unclear. In this paper, the authors
define the essential cis-acting element inPDF1.2 promoter responsive to methyl jasmonate (MeJA) through fragment deletions and site-directed mutageneses combiningAgrobacterium-mediated transient reporter gene expression in tobacco leaves. Firstly, the MeJA inducible expression ofPDF1.2 was confirmed by using the upstream −1.86 kb fragment ofPDF1.2 gene. Secondly, the upstream −300–−243 bp fragment of the promoter was evidenced to respond to MeJA. To further characterize
this promoter region, three point mutations were introduced into the −300–−243 bp fragment of the promoter. This result showed
that the mutation of GCC box abolished MeJA induction, whereas the mutations of the G box-like and the imperfect palindrome
sequence did not significantly decrease MeJA inducible effect, indicating that GCC box inPDF1.2 is essential for MeJA induction. The sufficient responsiveness to MeJA of this GCC box was further investigated by 4×GCC
fused upstream to the CaMV 35S minimal promoter. This result suggested that the fused promoter was able to activate reporter
gene expression in response to MeJA. Thus these results indicate that the GCC box inPDF1.2 is an essential and sufficient element to confer MeJA induction.
KeywordsAgroinfiltation-GCC box-MeJA-PDF1.2 promoter-
cis-acting element
Chinese Science Bulletin 04/2012; 49(23):2476-2480. · 1.32 Impact Factor
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ABSTRACT: Rice (Oryza sativa L.) is a warm-season plant exposed to various stresses. Low temperature is an important factor limiting extension of rice cultivation areas and productivity. Previously, we have demonstrated that tomato ERF protein TERF2 enhances freezing tolerance of transgenic tobacco and tomato plants. Herein, we report that overexpression of TERF2 enhances transgenic rice tolerance to cold without affecting growth or agronomic traits. Physiological assays revealed that TERF2 could not only increase accumulation of osmotic substances and chlorophyll, but also reduce reactive oxygen species (ROS) and malondialdehyde (MDA) content and decrease electrolyte leakage in rice under cold stress. Further analysis of gene expression showed that TERF2 could activate expression of cold-related genes, including OsMyb, OsICE1, OsCDPK7, OsSODB, OsFer1, OsTrx23, and OsLti6, in transgenic rice plants under natural condition or cold stress. Thus, our findings demonstrated that TERF2 modulated expression of stress-related genes and a series of physiological adjustments under cold stress, indicating that TERF2 might have important regulatory roles in response to abiotic stress in rice and possess potential utility in improving crop cold tolerance.
Transgenic Research 12/2010; 20(4):857-66. · 2.75 Impact Factor
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Limin Yang,
Guozhong Zhao,
Weihong Li,
Yufeng Liu,
Xiaoxi Shi,
Xinfeng Jia,
Kui Zhao, Xiangyang Lu,
Yizhuang Xu,
Datao Xie,
Jinguang Wu,
Jia'er Chen
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ABSTRACT: In this paper several polycrystalline molecules with sulfonate groups and some of their metal complexes, including DL-homocysteic acid (DLH) and its Sr- and Cu-complexes, pyridine-3-sulphonic acid and its Co- and Ni-complexes, sulfanilic acid and L-cysteic acid were investigated using THz time-domain methods at room temperature. The results of THz absorption spectra show that the molecules have characteristic bands in the region of 0.2-2.7 THz (6-90 cm(-1)). THz technique can be used to distinguish different molecules with sulfonate groups and to determine the bonding of metal ions and the changes of hydrogen bond networks. In the THz region DLH has three bands: 1.61, 1.93 and 2.02 THz; and 0.85, 1.23 and 1.73 THz for Sr-DLH complex, 1.94 THz for Cu-DLH complex, respectively. The absorption bands of pyridine-3-sulphonic acid are located at 0.81, 1.66 and 2.34 THz; the bands at 0.96, 1.70 and 2.38 THz for its Co-complex, 0.76, 1.26 and 1.87 THz for its Ni-complex. Sulphanilic acid has three bands: 0.97, 1.46 and 2.05 THz; and the absorption bands of l-cysteic acid are at 0.82, 1.62, 1.87 and 2.07 THz, respectively. The THz absorption spectra after complexation are different from the ligands, which indicate the bonding of metal ions and the changes of hydrogen bond networks. M-O and other vibrations appear in the FIR region for those metal-ligand complexes. The bands in the THz region were assigned to the rocking, torsion, rotation, wagging and other modes of different groups in the molecules. Preliminary assignments of the bands were carried out using Gaussian program calculation.
Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 10/2009; 73(5):884-91. · 2.10 Impact Factor
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ABSTRACT: Drought and high-salinity are the important constraints that severely affect plant development and crop yield worldwide. It has been established that ethylene response factor (ERF) proteins play important regulatory roles in plant response to abiotic and biotic stresses. Our previous researches have revealed that transgenic tobacco over-expressing TERF1 (encoding a tomato ERF protein) showed enhanced tolerance to abiotic stress. Here, we further investigate the function of TERF1 in transgenic rice. Compared with the wild-type plants, overexpression of TERF1 resulted in an increased tolerance to drought and high-salt in transgenic rice. And the enhanced tolerance may be associated with the accumulation of proline and the decrease of water loss. Furthermore, TERF1 can effectively regulate the expression of stress-related functional genes Lip5, Wcor413-l, OsPrx and OsABA2, as well as regulatory genes OsCDPK7, OsCDPK13 and OsCDPK19 under normal growth conditions. Our analyses of cis-acting elements show that there exist DRE/CRT and/or GCC-box existing in TERF1 targeted gene promoters. Our results revealed that ectopic expression of TERF1 in rice caused a series of molecular and physiological alterations and resulted in the transgenic rice with enhanced tolerance to abiotic stress, indicating that TERF1 might have similar regulatory roles in response to abiotic stress in tobacco and rice.
Plant Cell Reports 10/2008; 27(11):1787-95. · 2.27 Impact Factor
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Limin Yang,
Hongqi Sun,
Shifu Weng,
Kui Zhao,
Liangliang Zhang,
Guozong Zhao,
Yugang Wang,
Yizhuang Xu, Xiangyang Lu,
Cunlin Zhang,
Jinguang Wu,
Chen Jia'er
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ABSTRACT: In this work, THz absorption spectra of some saccharides and their metal complexes were measured. The main purpose of this work is to investigate the M-O vibrations, intermolecular and intramolecular hydrogen bonds and other vibrations in the FIR region using powerful spectroscopic techniques adopting the metal-sugar complexes prepared in our laboratory. The M-O vibrations in the FIR spectra of metal-sugar complexes indicate the formation of metal complexes. The THz spectrum of glucose below 100cm(-1) was measured at first to confirm the THz experimental method. Characteristic absorption bands in the spectra of various samples are observed. THz spectra of saccharides below 100cm(-1) often have several absorption bands, and different saccharides have various absorption peaks in the THz region, which may be used to distinguish different saccharides. The differences in the number of bands observed are related to different structures of the samples, and these absorption bands are related to the collective motion of molecules. But the THz spectra of their metal complexes are different from the ligands, and no band appears in the region below 50cm(-1) at the present experimental condition, which indicates that THz spectroscopy may also be helpful to identify the formation of metal-sugar complexes, and the changes after complexation in the THz spectra below 100cm(-1) may be related to different metal ions. The metal-sugar complexes with similar crystal structures resemble mid-IR spectra, but their THz spectra may have some differences.
Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 02/2008; 69(1):160-6. · 2.10 Impact Factor
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ABSTRACT: Ethylene responsive factors (ERFs) are important plant-specific transcription factors, some of which have been demonstrated to interact with the ethylene-responsive GCC box and the dehydration-responsive element (DRE); however, data on the roles of ERF proteins in connection with various signaling pathways are limited. In this research, we used the GCC box, an essential cis-acting element responsive to ethylene and methyl jasmonate (MeJA), as bait in a yeast one-hybrid system to isolate transcription factors from tomato (Lycopersicon esculentum Mill.). One of the cDNAs, which was designated Jasmonate and Ethylene Response Factor 1 (JERF1), encodes an ERF protein, containing a conserved ERF DNA-binding motif and functioning as a transcriptional activator in yeast through targeting to the nucleus in onion (Allium cepa L.) epidermal cells. Biochemical analysis revealed that JERF1 bound not only to the GCC box but also to the DRE sequence. Expression of the JERF1 gene in tomato was induced by ethylene, MeJA, abscisic acid (ABA) and salt treatment, indicating that JERF1 might act as a connector among different signal transduction pathways. Further research with transgenic JERF1 tobacco (Nicotiana tabacum L.) plants indicated that overexpressing JERF1 activated expression of GCC box-containing genes such as osmotin, GLA, Prb-1b and CHN50 under normal growth conditions, and subsequently resulted in enhanced tolerance to salt stress, suggesting that JERF1 modulates osmotic tolerance by activation of downstream gene expression through interaction with the GCC box or DRE.
Planta 01/2005; 220(2):262-70. · 3.00 Impact Factor
