Coordinated Activation of Programmed Cell Death and Defense Mechanisms in Transgenic Tobacco Plants Expressing a Bacterial Proton Pump.

Hydrogen peroxide (H2O2) has been implicated in the induction of plant defense genes and programmed cell death. Expression of a chimeric fungal glucose oxidase (GO) gene driven by a pathogen- and wound-inducible promoter was evaluated in transgenic tobacco and canola as a possible tool for engineering plant cell death and defense gene induction. Expression of this gene under the control of a peroxidase gene promoter resulted in the accumulation of relatively low levels of H2O2 in the young leaves of transgenic tobacco plants and this was not sufficient to cause any visible cell death and defense gene induction as measured by PR-1a mRNA induction. Older leaves of transgenic tobacco plants, however, exhibited visible necrotic lesions and constitutively expressed PR-1a mRNA when grown under high light conditions. Inoculation of cotyledons of control and transgenic canola with Leptosphaeria maculans resulted in rapid cotyledon senescence in the transgenic plants. Strong activators of the peroxidase promoter, i.e., wounding and inoculation of transgenic plants with Cercospora nicotianae, were not sufficient to trigger any additional visible cell death in transgenic tobacco plants, compared with controls. However, when exogenous glucose was supplied to transgenic tissue, massive cell death and PR-1a gene induction were observed in tobacco. Exogenously applied salicylic acid further increased the rate and extent of cell death. Our results suggest that efficacy of GO expression for the induction of cell death is restricted by glucose supply in the plants and are consistent with a role for salicylic acid in the potentiation of plant cell death by H2O2.

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Transformation of Human Alpha-lactalbumin Gene into Tobacco and Improvement of Cysteine Contents in Transgenic Tobacco Plants

Acta Botanica Yunnanica ◽

10.3724/sp.j.1143.2008.00457 ◽

2009 ◽

Vol 30 (4) ◽

pp. 457-463

Author(s):

Yi-Qun WANG

Keyword(s):

Transgenic Tobacco ◽

Transgenic Tobacco Plants ◽

Tobacco Plants ◽

Alpha Lactalbumin

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Production of an active recombinant thrombomodulin derivative in transgenic tobacco plants and suspension cells

Transgenic Research ◽

10.1007/s11248-004-8082-8 ◽

2005 ◽

Vol 14 (3) ◽

pp. 251-259 ◽

Cited By ~ 21

Author(s):

Helga Schinkel ◽

Andreas Schiermeyer ◽

Raphael Soeur ◽

Rainer Fischer ◽

Stefan Schillberg

Keyword(s):

Transgenic Tobacco ◽

Transgenic Tobacco Plants ◽

Suspension Cells ◽

Tobacco Plants ◽

Recombinant Thrombomodulin

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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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