Pest and disease resistance enhanced by heterologous suppression of a Nicotiana plumbaginifolia cytochrome P450 gene

Smigocki, Ann C.; Wilson, D. R.

doi:10.1007/s10529-004-4615-8

Cited by 16 publications

(12 citation statements)

References 14 publications

(21 reference statements)

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“…Petit Havana SR1 that carries the ipt gene fused to the CaMV 35S promoter (32); Ntx+ipt, N. tabacum L. cv. Xanthinc with the ipt gene fused to the wound-inducible proteinase inhibitor II promoter (28,30); and the Npl+ipt, N. plumbaginifolia Viv. 43A, where the ipt is under the control of light-inducible Rubisco small subunit protein promoter (34).…”

Section: Plants and Pathogensmentioning

confidence: 99%

“…In senescing leaves, leaf cytokinin levels are reduced, and external applications of cytokinins are well-known to delay tissue senescence. Transgenic plants that express the bacterial ipt (isopentenyl transferase) gene that catalyzes the synthesis of cytokinin exhibit delayed senescence (10,27,28) and increased insect and microbial resistance (29,30,32). In this paper, transgenic tobacco plants with constitutive or inducible promoters that overproduce cytokinins are utilized to analyze their response to infections with compatible and incompatible Pseudomonas spp.…”

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confidence: 99%

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Transgenic Production of Cytokinin Suppresses Bacterially Induced Hypersensitive Response Symptoms and Increases Antioxidative Enzyme Levels in Nicotiana spp.

Barna¹,

Smigocki²,

Baker³

2008

Phytopathology®

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Responses of cytokinin overproducing transgenic Nicotiana plants to infections with compatible and incompatible Pseudomonas syringae pathovars were compared. Plants used were transformed with the ipt(isopentenyl transferase) gene that catalyzes the synthesis of cytokinin. In cytokinin overproducing lines that carry the ipt gene fused to the CaMV 35S (Nt+ipt), the wound-inducible proteinase inhibitor II (Ntx+ipt), or the light-inducible Rubisco small subunit protein (Npl+ipt) promoter, development of the hypersensitive response (HR) after infection with incompatible bacteria (P. syringae pv. tomato) was significantly inhibited as compared to the untransformed (Nt) controls. Over a 12 h period following inoculation, P. syrinage pv. tomato populations were slightly reduced in leaves of the cytokinin-overproducing Nt-ipt line compared with the Nt control. When the compatible P. syringae. pv. tabaci was used to infect the ipt transformed lines, slight or no significant differences in necrosis development were observed. Following infection, the titer of P. syringae pv. tabaci increased rapidly in both the transgenic and control lines but was higher in Nt+ipt plants. Leaf superoxide dismutase and catalase enzyme activities were about 60% higher in ipt leaf extracts than in the controls. This augmented antioxidant capacity likely decreased the amount of H(2)O(2) that may be associated with the higher tolerance of plants to pathogen-induced necrosis. In addition, the Nt+ipt lines had a significantly lower molar ratio of free sterols to phospholipids. The more stable membrane lipid composition and the higher antioxidant capacity likely contributed to the suppressed HR symptoms in the cytokinin overproducing Nt+ipt plants. In conclusion, the overproduction of cytokinins in tobacco appears to suppress the HR symptoms induced by incompatible bacteria.

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Section: Plants and Pathogensmentioning

confidence: 99%

mentioning

confidence: 99%

Transgenic Production of Cytokinin Suppresses Bacterially Induced Hypersensitive Response Symptoms and Increases Antioxidative Enzyme Levels in Nicotiana spp.

Barna¹,

Smigocki²,

Baker³

2008

Phytopathology®

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“…Heterologous gene expression provides a means of examining the defensive role of metabolites in planta (Duan et al, 1996;Smigocki and Wilson, 2004;Zavala et al, 2004b). Introducing a Ser-type PI gene from potato (Solanum tuberosum) into rice (Oryza sativa) resulted in a new insect-resistant rice cultivar (Duan et al, 1996).…”

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confidence: 99%

Silencing Geranylgeranyl Diphosphate Synthase inNicotiana attenuataDramatically Impairs Resistance to Tobacco Hornworm

et al. 2007

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In bioassays with artificial diets, the 17-hydroxygeranyllinalool diterpenoid glycosides (HGL-DTGs) of Nicotiana attenuata function as antifeedants for the plant's adapted herbivore, tobacco hornworm (Manduca sexta). To determine whether HGLDTGs have a defensive function in planta, we suppressed HGL-DTG production by silencing the source of the geranylgeranyl diphosphates (GGPPs) required for geranyllinalool biosynthesis, a key intermediate. We used virus-induced gene silencing to suppress transcript levels of GGPP synthase gene (Naggpps) and farnesyl diphosphate (FPP) synthase gene (Nafpps), northern blotting and real-time polymerase chain reaction to quantify transcript accumulations, and radio gas chromatography to analyze prenyltransferase specificity. Silencing Nafpps had no effect on the accumulation of HGL-DTGs but decreased leaf steroid content, demonstrating that DTG-synthesizing enzymes do not use GGPP derived from FPP and confirming FPP's role as a steroid precursor. Unlike plants silenced in the phytoene desaturase gene (Napds), which rapidly bleached, Naggppssilenced plants had reduced HGL-DTG but not carotenoids or chlorophyll contents, demonstrating that Naggpps supplies substrates for GGPP biosynthesis for HGL-DTGs, but not for phytoene or phytol. Expression of Naggpps in Escherichia coli revealed that the recombinant protein catalyzes the GGPP synthesis from isopentenyl diphosphate and dimethylallyl diphosphate. When fed on silenced plants, hornworm larvae gained up to 3 times more mass than those that fed on empty vector control plants or plants silenced in Nafpps, the trypsin protease inhibitor gene, or the putrescine N-methyltransferase gene. We conclude that HGL-DTGs or other minor undetected diterpenoids derived from GGPP function as direct defenses for N. attenuata and are more potent than nicotine or trypsin protease inhibitors against attack by hornworm larvae.

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“…These variability's and the complex classification of CYTOCHROME P450 genes leads to diverse functions in plants [50]. Usually, these genes are involved in secondary metabolite biosynthesis [50] and defense responses against various abiotic and biotic stresses [50,51]. Plant CYTOCHROME genes activate during stress conditions and accumulate antioxidant flavonoids [12] to alleviate the negative effects of environmental stress [52].…”

Section: Discussionmentioning

confidence: 99%

CsCYT75B1, a Citrus CYTOCHROME P450 Gene, Is Involved in Accumulation of Antioxidant Flavonoids and Induces Drought Tolerance in Transgenic Arabidopsis

Rao

Tang

et al. 2020

Antioxidants

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CYTOCHROME P450s genes are a large gene family in the plant kingdom. Our earlier transcriptome data revealed that a CYTOCHROME P450 gene of Citrus sinensis (CsCYT75B1) was associated with flavonoid metabolism and was highly induced after drought stress. Here, we characterized the function of CsCYT75B1 in drought tolerance by overexpressing it in Arabidopsis thaliana. Our results demonstrated that the overexpression of the CsCYT75B1 gene significantly enhanced the total flavonoid contents with increased antioxidant activity in transgenic Arabidopsis. The gene expression results showed that several genes that are responsible for the biosynthesis of antioxidant flavonoids were induced by 2-12 fold in transgenic Arabidopsis lines. After 14 days of drought stress, all transgenic lines displayed an enhanced tolerance to drought stress along with accumulating antioxidant flavonoids with lower superoxide radicals and reactive oxygen species (ROS) than wild type plants. In addition, drought-stressed transgenic lines possessed higher antioxidant enzymatic activities than wild type transgenic lines. Moreover, the stressed transgenic lines had significantly lower levels of electrolytic leakage than wild type transgenic lines. These results demonstrate that the CsCYT75B1 gene of sweet orange functions in the metabolism of antioxidant flavonoid and contributes to drought tolerance by elevating ROS scavenging activities.

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Pest and disease resistance enhanced by heterologous suppression of a Nicotiana plumbaginifolia cytochrome P450 gene

Cited by 16 publications

References 14 publications

Transgenic Production of Cytokinin Suppresses Bacterially Induced Hypersensitive Response Symptoms and Increases Antioxidative Enzyme Levels in Nicotiana spp.

Transgenic Production of Cytokinin Suppresses Bacterially Induced Hypersensitive Response Symptoms and Increases Antioxidative Enzyme Levels in Nicotiana spp.

Silencing Geranylgeranyl Diphosphate Synthase inNicotiana attenuataDramatically Impairs Resistance to Tobacco Hornworm

CsCYT75B1, a Citrus CYTOCHROME P450 Gene, Is Involved in Accumulation of Antioxidant Flavonoids and Induces Drought Tolerance in Transgenic Arabidopsis

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