Preparation of Graphene Oxide and Its Mechanism in Promoting Tomato Roots Growth

Graphene oxide is a new kind of nanomaterial. The graphene oxide was prepared and its quality detected by atomic force microscopy (AFM) and transmission electron microscopy (TEM), for better understanding of effects of the nanomaterial on plants. Wild type (WT) tomato (Solanum lycopersicum) germplasm ‘New Yorker’ and corresponding transgenic plants (Prd29A::LeNCED1) were treated with prepared graphene oxide. 9-cis-epoxycarotenoid dioxygenase (NCED) is a key gene for ABA biosynthesis and overexpression of the NCED resulted in ABA accumulation and higher drought tolerance. Seminal root length in the WT tomato was longer than that in the control samples when the seedlings were treated with 20 mg/L graphene oxide for 15 days. In contrast, the same treatment resulted in shorter seminal root length in the transgenic plants compared with control samples. The graphene oxide treatments led to lower Superoxide Dismutase (SOD), Peroxidase (POD), Catalase (CAT) activity and Malondialdehyde (MDA) content in the WT and transgenic plants. 20 mg/L graphene oxide treatment also affected the transcript levels of IAA7, IAA4 and IAA10 but the effect on the wild type and corresponding transgenic plants was different. IAA4 transcription level decreased both in the WT and Prd29A::LeNCED1 transgenic plants while the IAA7 transcription level decreased in the transgenic plants and increased in the WT tomato. The IAA10 transcription level decreased in the WT tomato and increased in the Prd29A::LeNCED1 transgenic plants. Graphene oxide treatments resulted in higher transcription level of ABCG25 and ABCG40 in the WT plants but had no significant effect on transgenic plants. The transcription level of NCED in the WT and Prd29A::LeNCED1 transgenic plants treated with graphene oxide increased significantly, however, it was higher in the transgenic plants than in the WT tomato after 15 d treatment, indicating that the graphene oxide activated the rd29A promoter as does drought and salt. The HD-ZIP transcription level only decreased significantly in the treated Prd29A::LeNCED1 transgenic plants. All these results suggested that there was a crosstalk between ABA and graphene oxide and the graphene oxide affected plant growth through the ABA and IAA pathway.

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Overexpression of the pitaya phosphoethanolamine N-methyltransferase gene (HpPEAMT) enhanced simulated drought stress in tobacco

Plant Cell Tissue and Organ Culture (PCTOC) ◽

10.1007/s11240-021-02040-3 ◽

2021 ◽

Author(s):

Ai-Hua Wang ◽

Lan Yang ◽

Xin-Zhuan Yao ◽

Xiao-Peng Wen

Keyword(s):

Drought Stress ◽

Stress Response ◽

Transgenic Plants ◽

Drought Tolerance ◽

Transgenic Tobacco ◽

Sequence Similarity ◽

Amino Acid Sequence Similarity ◽

Transgenic Tobacco Plants ◽

Wild Type ◽

Tobacco Plants

AbstractPhosphoethanolamine N-methyltransferase (PEAMTase) catalyzes the methylation of phosphoethanolamine to produce phosphocholine and plays an important role in the abiotic stress response. Although the PEAMT genes has been isolated from many species other than pitaya, its role in the drought stress response has not yet been fully elucidated. In the present study, we isolated a 1485 bp cDNA fragment of HpPEAMT from pitaya (Hylocereus polyrhizus). Phylogenetic analysis showed that, during its evolution, HpPEAMT has shown a high degree of amino acid sequence similarity with the orthologous genes in Chenopodiaceae species. To further investigate the function of HpPEAMT, we generated transgenic tobacco plants overexpressing HpPEAMT, and the transgenic plants accumulated significantly more glycine betaine (GB) than did the wild type (WT). Drought tolerance trials indicated that, compared with those of the wild-type (WT) plants, the roots of the transgenic plants showed higher drought tolerance ability and exhibited improved drought tolerance. Further analysis revealed that overexpression of HpPEAM in Nicotiana tabacum resulted in upregulation of transcript levels of GB biosynthesis-related genes (NiBADH, NiCMO and NiSDC) in the leaves. Furthermore, compared with the wild-type plants, the transgenic tobacco plants displayed a significantly lower malondialdehyde (MDA) accumulation and higher activities of the superoxide dismutase (SOD) and peroxidase (POD) antioxidant enzymes under drought stress. Taken together, our results suggested that HpPEAMT enhanced the drought tolerance of transgenic tobacco.

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First genome edited poinsettias: targeted mutagenesis of flavonoid 3′-hydroxylase using CRISPR/Cas9 results in a colour shift

Plant Cell Tissue and Organ Culture (PCTOC) ◽

10.1007/s11240-021-02103-5 ◽

2021 ◽

Author(s):

Daria Nitarska ◽

Robert Boehm ◽

Thomas Debener ◽

Rares Calin Lucaciu ◽

Heidi Halbwirth

Keyword(s):

Transgenic Plants ◽

Genome Editing ◽

Ornamental Plants ◽

Targeted Mutagenesis ◽

Cloning And Expression ◽

Euphorbia Pulcherrima ◽

Loss Of Function ◽

Wild Type ◽

Promising Tool ◽

Reddish Orange

AbstractThe CRISPR/Cas9 system is a remarkably promising tool for targeted gene mutagenesis, and becoming ever more popular for modification of ornamental plants. In this study we performed the knockout of flavonoid 3′-hydroxylase (F3′H) with application of CRISPR/Cas9 in the red flowering poinsettia (Euphorbia pulcherrima) cultivar ‘Christmas Eve’, in order to obtain plants with orange bract colour, which accumulate prevalently pelargonidin. F3′H is an enzyme that is necessary for formation of cyanidin type anthocyanins, which are responsible for the red colour of poinsettia bracts. Even though F3′H was not completely inactivated, the bract colour of transgenic plants changed from vivid red (RHS 45B) to vivid reddish orange (RHS 33A), and cyanidin levels decreased significantly compared with the wild type. In the genetically modified plants, an increased ratio of pelargonidin to cyanidin was observed. By cloning and expression of mutated proteins, the lack of F3′H activity was confirmed. This confirms that a loss of function mutation in the poinsettia F3′H gene is sufficient for obtaining poinsettia with orange bract colour. This is the first report of successful use of CRISPR/Cas9 for genome editing in poinsettia.

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Degradation of trinitrotoluene by transgenic nitroreductase in Arabidopsis plants

Plant Soil and Environment ◽

10.17221/655/2017-pse ◽

2018 ◽

Vol 64 (No. 8) ◽

pp. 379-385 ◽

Cited By ~ 7

Author(s):

Zhu Bo ◽

Han Hongjuan ◽

Fu Xiaoyan ◽

Li Zhenjun ◽

Gao Jianjie ◽

...

Keyword(s):

Transgenic Plants ◽

Transgenic Arabidopsis ◽

Environmental Pollutant ◽

Specific Rate ◽

Wild Type Plant ◽

Wild Type ◽

Fresh Weight ◽

Human Carcinogen ◽

Specific Rate Constant ◽

Nitroreductase Activity

The explosive 2,4,6-trinitrotoluene (TNT) is a highly toxic and persistent environmental pollutant. TNT is toxic to many organisms, it is known to be a potential human carcinogen, and is persistent in the environment. This study presents a system of phytoremediation by Arabidopsis plants developed on the basis of overexpression of NAD(P)H-flavin nitroreductase (NFSB) from the Sulfurimonas denitrificans DSM1251. The resulting transgenic Arabidopsis plants demonstrated significantly enhanced TNT tolerance and a strikingly higher capacity to remove TNT from their media. The highest specific rate constant of TNT disappearance rate was 1.219 and 2.297 mL/g fresh weight/h for wild type and transgenic plants, respectively. Meanwhile, the nitroreductase activity in transgenic plant was higher than wild type plant. All this indicates that transgenic plants show significantly enhanced tolerances to TNT; transgenic plants also exhibit strikingly higher capabilities of removing TNT from their media and high efficiencies of transformation.

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MNB1 gene is involved in regulating the iron-deficiency stress response in Arabidopsis thaliana

10.21203/rs.3.rs-833563/v1 ◽

2021 ◽

Author(s):

Hui Song ◽

Feng Chen ◽

Xi Wu ◽

Min Hu ◽

Qingliu Geng ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Arabidopsis Thaliana ◽

Normal Growth ◽

Developmental Changes ◽

Fe Deficiency ◽

Oxygen Species ◽

Mineral Element ◽

Wild Type ◽

Transcription Level ◽

Fe Uptake

Abstract Abstract Iron (Fe) is an indispensable mineral element for normal growth of plants. Fe deficiency induces a complex series of responses in plants, involving physiological and developmental changes, to increase Fe uptake from soil. However, the molecular mechanism involved in plant Fe-deficiency is not well understood. Here, we found that the MNB1 gene is involved in modulating Fe-deficiency response in Arabidopsis thaliana . The expression of MNB1 was inhabited by Fe-deficiency stress. Knockout of MNB1 led to enhanced Fe accumulation and tolerance, whereas the MNB1-overexpressing plants were sensitive to Fe-deficiency stress. Lower H 2 O 2 concentrations in mnb1 mutant plants were examined under Fe deficiency circumstances compared to wild-type. On the contray, higher H 2 O 2 concentrations were found in MNB1-overexpressing plants, which was adversely linked with malondialdehyde (MDA) concentrations. Furthermore, in mnb1 mutants, the transcription level of the Fe-uptake and translocation genes, FIT , IRT1 , FRO2 , Z IF , FRD3 , NAS4 , PYE and MYB72 , were considerably elevated during Fe-deficiency stress, resulting in higher Fe accumulation. Together, our findings show that the MNB1 gene negatively controls the Fe-deficiency response in Arabidopsis via modulating reactive oxygen species (ROS) levels and the ROS-mediated signaling pathway, thereby affecting the expression of Fe-uptake and translocation genes.

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Root Colonization by Agrobacterium tumefaciens Is Reduced in cel, attB,attD, and attR Mutants

Applied and Environmental Microbiology ◽

10.1128/aem.64.7.2341-2345.1998 ◽

1998 ◽

Vol 64 (7) ◽

pp. 2341-2345 ◽

Cited By ~ 52

Author(s):

Ann G. Matthysse ◽

Susan McMahan

Keyword(s):

Agrobacterium Tumefaciens ◽

Root Length ◽

Root Colonization ◽

Bacterial Pathogenesis ◽

Bacterial Suspension ◽

Cellulose Synthesis ◽

Wild Type ◽

Tomato Roots ◽

Extensive Growth ◽

Number Of Bacteria

ABSTRACT Root colonization by Agrobacterium tumefaciens was measured by using tomato and Arabidopsis thaliana roots dipped in a bacterial suspension and planted in soil. Wild-type bacteria showed extensive growth on tomato roots; the number of bacteria increased from 103 bacteria/cm of root length at the time of inoculation to more than 107 bacteria/cm after 10 days. The numbers of cellulose-minus and nonattachingattB, attD, and attR mutant bacteria were less than 1/10,000th the number of wild-type bacteria recovered from tomato roots. On roots of A. thalianaecotype Landsberg erecta, the numbers of wild-type bacteria increased from about 30 to 8,000 bacteria/cm of root length after 8 days. The numbers of cellulose-minus and nonattaching mutant bacteria were 1/100th to 1/10th the number of wild-type bacteria recovered after 8 days. The attachment of A. tumefaciens to cut A. thaliana roots incubated in 0.4% sucrose and observed with a light microscope was also reduced with cel andatt mutants. These results suggest that cellulose synthesis and attachment genes play a role in the ability of the bacteria to colonize roots, as well as in bacterial pathogenesis.

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Overexpression of Plasma Membrane H+-ATPase in Guard Cells Enhances Light-Induced Stomatal Opening, Photosynthesis, and Plant Growth in Hybrid Aspen

Frontiers in Plant Science ◽

10.3389/fpls.2021.766037 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shigeo Toh ◽

Naoki Takata ◽

Eigo Ando ◽

Yosuke Toda ◽

Yin Wang ◽

...

Keyword(s):

Plasma Membrane ◽

Transgenic Plants ◽

Woody Plants ◽

Stem Elongation ◽

Guard Cells ◽

Gus Expression ◽

Stomatal Opening ◽

Wild Type ◽

Exchange System ◽

Gas Exchange System

Stomata in the plant epidermis open in response to light and regulate CO2 uptake for photosynthesis and transpiration for uptake of water and nutrients from roots. Light-induced stomatal opening is mediated by activation of the plasma membrane (PM) H+-ATPase in guard cells. Overexpression of PM H+-ATPase in guard cells promotes light-induced stomatal opening, enhancing photosynthesis and growth in Arabidopsis thaliana. In this study, transgenic hybrid aspens overexpressing Arabidopsis PM H+-ATPase (AHA2) in guard cells under the strong guard cell promoter Arabidopsis GC1 (AtGC1) showed enhanced light-induced stomatal opening, photosynthesis, and growth. First, we confirmed that AtGC1 induces GUS expression specifically in guard cells in hybrid aspens. Thus, we produced AtGC1::AHA2 transgenic hybrid aspens and confirmed expression of AHA2 in AtGC1::AHA2 transgenic plants. In addition, AtGC1::AHA2 transgenic plants showed a higher PM H+-ATPase protein level in guard cells. Analysis using a gas exchange system revealed that transpiration and the photosynthetic rate were significantly increased in AtGC1::AHA2 transgenic aspen plants. AtGC1::AHA2 transgenic plants showed a>20% higher stem elongation rate than the wild type (WT). Therefore, overexpression of PM H+-ATPase in guard cells promotes the growth of perennial woody plants.

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The free proline levels in transgenic sunflower (Helianthus annuus L.) T3 plants with double-stranded proline dehydrogenase gene RNA-suppressor

Faktori eksperimental'noi evolucii organizmiv ◽

10.7124/feeo.v20.766 ◽

1970 ◽

pp. 211-214 ◽

Cited By ~ 1

Author(s):

A. G. Komisarenko ◽

S. I. Mykhalska

Keyword(s):

Transgenic Plants ◽

Helianthus Annuus ◽

High Elevation ◽

Stress Conditions ◽

Free Proline ◽

Wild Type ◽

Helianthus Annuus L ◽

Osmotic Tolerance ◽

Dehydrogenase Gene ◽

Plant Shoots

Aim. The investigation of the T3 transgenic sunflower plants osmotic tolerance there were developed. The levels of free proline in plant shoots and roots were estimated. Methods. Mature sunflower plants (T3 and wild type) were cultured in standard pots. Those genotypes were tested during 12-day artificial drying. The levels of free proline in plant shoots and roots were measured. Results. The proline contents in transgenic plants preferred those parameters of control plants both under normal and stress conditions. The proline levels in shoots and roots increased in all genotypes cultivated under stress conditions. The shoot/root proline ratio of control plants was constant during whole experiment, while in T3 plants this parameter changed due to high elevation in roots. Conclusions. The changes of shoot/root proline ratio of T3 plants were the result of free proline transfer among plant organs. Keywords: Helianthus annuus L., transgenic plants, L-proline, shoot/root proline ratio.

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Contribution of the TROLC gene to the regulation of tobacco growth in response to stress factors.

Biomics ◽

10.31301/2221-6197.bmcs.2021-25 ◽

2021 ◽

Vol 13 (3) ◽

pp. 360-367

Author(s):

B.R. Kuluev ◽

Kh.G. Musin ◽

E.A. Baimuhametova

Keyword(s):

Transgenic Plants ◽

Root Growth ◽

Shoot Growth ◽

Growth Parameters ◽

Cadmium Acetate ◽

Stress Factors ◽

Wild Type ◽

Abiotic Stress Factors ◽

Negative Effect ◽

Response To Stress

The trolC gene refers to plast genes that have entered the genome of Nicotiana tabacum as a probable result of horizontal transfer from Agrobacterium rhizogenes. It was shown that the trolC gene is expressed in young tissues of wild type tobacco; however, the physiological functions of the product of this gene remain largely unknown. The aim of our work was to obtain transgenic tobacco plants expressing a fragment of the trolC gene under the control of the 35SCaMV promoter in an antisense orientation and to assess the growth parameters of their roots under the action of abiotic stress factors. For morphometric analysis, 8 lines of transgenic plants were used. The analysis of root growth under the action of sodium chloride (100 mM), cadmium acetate (100 μM) and hypothermia (12°C) was conducted. Transgenic plants were characterized by improved shoot growth parameters under normal conditions. The roots of transgenic plants grew more slowly under normal conditions and under the action of cadmium and hypothermia than in wild type plants. The product of trolC gene has a negative effect on shoot growth, a positive effect on root growth, and also participates in the regulation and maintenance of root growth under the action of cadmium and hypothermia.

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Efficient induction of haploid plants in wheat by editing of TaMTL using an optimized Agrobacterium-mediated CRISPR system

Journal of Experimental Botany ◽

10.1093/jxb/erz529 ◽

2019 ◽

Vol 71 (4) ◽

pp. 1337-1349 ◽

Cited By ~ 11

Author(s):

Huiyun Liu ◽

Ke Wang ◽

Zimiao Jia ◽

Qiang Gong ◽

Zhishan Lin ◽

...

Keyword(s):

Transgenic Plants ◽

High Efficiency ◽

Seed Set ◽

Large Fragment ◽

Wild Type ◽

Haploid Induction ◽

Wheat Grains ◽

Editing Efficiency ◽

Efficient Induction ◽

Endogenous Genes

Abstract The use of CRISPR/LbCpf1 and CRISPR/xCas9 systems in wheat have not yet been reported. In this study, we compared the efficiencies of three CRISPR editing systems (SpCas9, LbCpf1, and xCas9), and three different promoters (OsU6a, TaU3, and TaU6) that drive single-guide (sg)RNA, which were introduced into wheat via Agrobacterium-mediated transformation. The results indicated that TaU3 was a better choice than OsU6a or TaU6. The editing efficiency was higher using two sgRNAs than one sgRNA, and mutants with a large fragment deletion between the two sgRNAs were produced. The LbCpf1 and xCas9 systems could both be used successfully. Two endogenous genes, TaWaxy and TaMTL, were edited with high efficiency by the optimized SpCas9 system, with the highest efficiency (80.5%) being achieved when using TaU3 and two sgRNAs to target TaWaxy. Rates of seed set in the TaMTL-edited T0 transgenic plants were much lower than that of the wild-type. A haploid induction rate of 18.9% was found in the TaMTL-edited T1 plants using the CRISPR/SpCas9 system. Mutants with reverse insertion of the deleted sequences of TaMTL and TaWaxy between the two sgRNAs were identified in the edited T0 plants. In addition, wheat grains lacking embryos or endosperms were observed in the TaMTL-edited T1 generation.

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