Cucumber (Cucumis sativus) is an important vegetable crop in the world. Agrobacterium-mediated transgenic technology is an important way to study plant gene functions and improve varieties. In order to further accelerate the transgenic research and breeding process of cucumber, we described the progress and problems of Agrobacterium tumefaciens-mediated transgenic cucumber, from the influencing factors of cucumber regeneration ability, genetic transformation conditions and various additives in the process. We prospected for improving the genetic transformation efficiency and safety selection markers of cucumber, and hoped to provide reference for the research of cucumber resistance breeding and quality improvement.
Agrobacterium tumefaciens ; metabolism ; Breeding ; Cucumis sativus ; genetics ; microbiology ; Plants, Genetically Modified ; microbiology ; Research ; Transformation, Genetic

Production of reactive oxygen species (ROS) is a conserved immune response primarily mediated by NADPH oxidases (NOXs), also known in plants as respiratory burst oxidase homologs (RBOHs). Most microbe-associated molecular patterns (MAMPs) trigger a very fast and transient ROS burst in plants. However, recently, we found that lipopolysaccharides (LPS), a typical bacterial MAMP, triggered a biphasic ROS burst. In this study, we isolated mutants defective in LPS-triggered biphasic ROS burst (delt) in Arabidopsis, and cloned the DELT1 gene that was shown to encode RBOHD. In the delt1-2 allele, the antepenultimate residue, glutamic acid (E919), at the C-terminus of RBOHD was mutated to lysine (K). E919 is a highly conserved residue in NADPH oxidases, and a mutation of the corresponding residue E568 in human NOX2 has been reported to be one of the causes of chronic granulomatous disease. Consistently, we found that residue E919 was indispensable for RBOHD function in the MAMP-induced ROS burst and stomatal closure. It has been suggested that the mutation of this residue in other NADPH oxidases impairs the protein's stability and complex assembly. However, we found that the E919K mutation did not affect RBOHD protein abundance or the ability of protein association, suggesting that the residue E919 in RBOHD might have a regulatory mechanism different from that of other NOXs. Taken together, our results confirm that the antepenultimate residue E is critical for NADPH oxidases and provide a new insight into the regulatory mechanisms of RBOHD.
Agrobacterium tumefaciens/metabolism* ; Alleles ; Arabidopsis/metabolism* ; Arabidopsis Proteins/genetics* ; Gene Expression Regulation, Plant ; Genetic Techniques ; Humans ; Lipopolysaccharides/metabolism* ; Luminescence ; Mutation ; NADPH Oxidase 2/chemistry* ; NADPH Oxidases/genetics* ; Plant Stomata/metabolism* ; Protein Domains ; Reactive Oxygen Species/metabolism* ; Nicotiana/metabolism*

To develop a genetic transformation method of Aureobasidium pullulans and T-DNA insertion for high-efficient screening of polymalic acid (PMA) producing strain. Agrobacterium tumefaciens-AGL1, containing the selection genes encoding hygromycin B phosphotase or phosphinothricin acetyltranferase, was used to transform Aureobasidium pullulans CCTCC M2012223 and transformants were confirmed by colony PCR method. Transferred DNA (T-DNA) insertional mutants were cultured in microwell plate, and screened for high-titer PMA producing strain according to the pH response model. DNA walking was used to detect the insertion sites in the mutant. Results show that the selection markers could stably generated in the transformants, and 80 to 120 transformants could be found per 10(7) single cells. A high-titer PMA mutant H27 was obtained, giving a good PMA production caused by the disruption of phosphoglycerate mutase, that increased by 24.5% compared with the control. Agrobacterium tumefaciens-mediated transformation and high-efficient screening method were successfully developed, which will be helpful for genetic transformation of Aureobasidium pullulans and its functional genes discovery.
Agrobacterium tumefaciens ; Ascomycota ; genetics ; metabolism ; DNA, Bacterial ; Malates ; metabolism ; Polymerase Chain Reaction ; Polymers ; metabolism ; Transformation, Genetic

To explore the influence of low light on the synthesis of carotenoids, chlorophyll and the adaptability of transgenic plants with tomato Solanum lycopersicon L. GGPS2 gene, we constructed a vector containing a GGPS2 gene with green fluorescent protein (GFP) as report gene under the control of a cauliflower mosaic virus 35S promoter and introduced it into tobacco Nicotiana tabacum L. cv. Wisconsin 38 by Agrobacterium tumefaciens-mediated transformation. PCR analysis of the DNA from kanamycin resistant tobacco indicated that the transgenic tobacco containing the nptII gene, SlaGGPS2 gene and without contamination of Agrobacterium. We also detected the root tip of kanamycin resistant tobacco showing characteristic fluorescence. The contents of carotenoid, chlorophyll and photosynthesis of transgenic tobacco increased in comparison with wild tobacco after low light treatment. In addition, leaf mass per unit area, total dry weight, ratio of root to shoot in transgenic tobacco were all higher than that of the wild tobacco, which proved that the transgenic tobacco could increase the accumulation of biomass and promote it transport to root. The transgenic tobacco with SlaGGPS2 gene can increase the contents of carotenoid, chlorophyll, enhance the photosynthetic rate, promote the biomass accumulation and its distribution to root. Hence, the transgenic tobacco with SlaGGPS2 gene had increased low light tolerance and the SlaGGPS2 gene maybe can be used in other crops.
Agrobacterium tumefaciens ; Carotenoids ; analysis ; Chlorophyll ; analysis ; Gene Expression Regulation, Plant ; Genetic Vectors ; Light ; Lycopersicon esculentum ; genetics ; Photosynthesis ; Plants, Genetically Modified ; metabolism ; radiation effects ; Tobacco ; metabolism ; radiation effects

Withanolide A is a biologically active secondary metabolite occuring in roots and leaves of Withania somnifera. In the present study, adventitious roots from leaf explants of W. somnifera were induced for the production of withanolide-A by Agrobacterium tumefaciens strain C58C1 to obtain hair roots. Hair roots induction rate reached 30%. The withanolide A was determined by HPLC in different hair roots lines and different parts of W. somnifera. The average content of withanolide A in all hair roots lines were 1.96 times as high as that in wild-plant, the concentration of withanolide A in hair roots (1.783 mg x g(-1) dry weight) were 1.51 times as high as the roots of wild W. somnifera (1.180 mg x g(-1) dry weight), respectively. It is possible to obtain withanolide A from hair roots culture of W. somnifera.
Agrobacterium tumefaciens ; physiology ; Plant Extracts ; analysis ; biosynthesis ; Plant Roots ; chemistry ; growth & development ; metabolism ; microbiology ; Withania ; chemistry ; growth & development ; metabolism ; microbiology ; Withanolides ; analysis ; metabolism

PNS (Panax notoginseng saponins) is the main medical bioactive component in Panax notoginseng. The medical value of PNS cannot be extended because of its low production. With the deep study of saponins biosynthetic pathway, the control of PNS biosynthesis through metabolic engineering has gradually become possible. In this study, the Squalene synthase (SS) over-expression vector was established. By the way of agrobacterium-mediated method, the vector was transfered and integrated into the Panax notoginseng genome. The result of the PCR detection and the saponin content detection shows that over-expression SS is able to produce high level of Panax notoginseng saponins, and confirms the regulatory function of SS in the biosynthesis of ginsenosides in Panax notoginseng. It provides a theoretical basis and technical basis for the construction of PNS homologous or heterologous efficient expression system in the future.
Agrobacterium tumefaciens ; Amino Acid Sequence ; Cell Line ; Cloning, Molecular ; DNA, Complementary ; genetics ; Farnesyl-Diphosphate Farnesyltransferase ; genetics ; metabolism ; Gene Transfer Techniques ; Genetic Vectors ; genetics ; Panax notoginseng ; chemistry ; cytology ; genetics ; microbiology ; Plants, Genetically Modified ; chemistry ; cytology ; genetics ; microbiology ; Plants, Medicinal ; chemistry ; cytology ; genetics ; microbiology ; Saponins ; metabolism ; Transformation, Genetic

Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection.
Administration, Oral ; Agrobacterium tumefaciens ; Animals ; Antigens, Bacterial/genetics/metabolism ; Bacterial Vaccines/administration & dosage/adverse effects/*pharmacology ; Edema Disease of Swine/*immunology/microbiology ; Escherichia coli Infections/immunology/microbiology/*veterinary ; Escherichia coli Proteins/*genetics/metabolism ; Female ; Fimbriae Proteins/genetics/metabolism ; Genetic Engineering ; Intestines/immunology/microbiology/pathology ; Mice ; Mice, Inbred BALB C ; Models, Animal ; Plants, Genetically Modified/*genetics/metabolism ; Seeds/genetics/metabolism ; Shiga Toxin 2/genetics/metabolism ; Shiga-Toxigenic Escherichia coli/genetics/immunology/*pathogenicity ; Swine ; Tobacco/*genetics/metabolism ; Virulence Factors/genetics/metabolism

OBJECTIVETo establish an efficient genetic transformation system of Pinellia ternata.

METHODWith petioles from test-tube seedlings of P. ternata as explants, Agrobacterium tumefaciens mediation method was adopted to explore the effect of phenolic substances, A. tumefaciens's concentration, infection time, pre-incubation time and co-cultivation time on genetic transformation efficiency of P. ternata.

RESULT AND CONCLUSIONThe genetic transformation efficiency could be effectively enhanced by infecting in A. tumefaciens culture containing AS 40 mg x L(-1) for 15 min for three days. The petioles were put into the differentiation medium containing 150 mg x L(-1) Kan and 350 mg x L(-1) Carb to screening and cultivation. After around 30 days, microtubers could be observed at both sides of the petioles. Gus staining and PCR verification on the regenerated plants showed that the exogenous gene sHSP had been integrated into genome of P. ternata.

Agrobacterium tumefaciens ; genetics ; DNA, Plant ; genetics ; Genetic Engineering ; methods ; Glucuronidase ; genetics ; metabolism ; Heat-Shock Proteins, Small ; genetics ; Pinellia ; genetics ; growth & development ; metabolism ; Plant Leaves ; genetics ; growth & development ; metabolism ; Plants, Genetically Modified ; Polymerase Chain Reaction ; Reproducibility of Results ; Tissue Culture Techniques ; methods ; Transformation, Genetic

In order to increase the expression level of target gene and to simplify the purifying process of separation and purification, we performed the transgenetic research of antigen VP7 gene into peanut via Agrobacterium tumefaciens. The plant binary expression vector is pBOG3VP7 harboring fusion gene oleosin-vp7, which is promoted by ole-promoter. Cotyledon nodes were used as transformation recipients. Transformed individuals were obtained through selection on medium containing 125 mg L-1 Kan. Integration of transgenes was assessed by PCR amplification and PCR-Southern blot hybridization. Taking pBOG3VP7 plasmid as positive control, non-transformed peanut as negative control. 6 plants among 11 plants grown up through seletion medium were detected by PCR and the rate of positive plants is 54.5%. PCR positive plants were further analysed by PCR-Southern blot hybridization. The results showed that 3 plants have DNA bloting bands. The results also showed that the foreign gene was integrated into genome of transformed peanuts. Elevated expression of rotavirus VP7 antigen in transgenic peanuts was a critical factor in the development of efficient and cheap plant oral vaccine.
Agrobacterium tumefaciens ; genetics ; Antigens, Viral ; biosynthesis ; genetics ; Arachis ; genetics ; metabolism ; Capsid Proteins ; biosynthesis ; genetics ; Plants, Genetically Modified ; genetics ; metabolism ; Rotavirus ; genetics ; immunology ; Transformation, Genetic ; Vaccines, Synthetic

OBJECTIVETo establish the transformation system of mulberry, and test its ability of quercetin biosynthesis.

METHODHairy roots of mulberry were obtained through infecting etiolated seedlings with Agrobacterium tumefaciens strain C58C1. The culture condition of hairy roots was optimized. The transformation of T-DNA was examined by PCR assay and quercetin content was determined by HPLC.

RESULTWhen infecting stem cutting of etiolated seedlings via C58C1 strain, the optimal transformation conditions were as follows: 10 minutes' infection, two-days pre-culture and co-culture, additional hydroxylacetosyringone (As) 100 mg x L(-1). The PCR examination result showed that rolB and rolC genes could be inserted into the hairy roots of mulberry. Hairy roots appeared in 10 days after infecting, the frequency of stems explants was up to 92% after 30 days culturing. After 50 days culturing in 1/2MS + 0.05 mg x L(-1) IBA liquid medium, the content of quercetin increased by 8. 5-fold.

CONCLUSIONHairy root culture system of Moraceae plants was established successfully for the first time. In addition, it also provides a foundation for further industrial production of active compounds such as quercetin.

Agrobacterium tumefaciens ; genetics ; metabolism ; Cells, Cultured ; DNA, Bacterial ; genetics ; Gene Targeting ; methods ; Genetic Vectors ; genetics ; metabolism ; Morus ; genetics ; metabolism ; microbiology ; Quercetin ; biosynthesis ; Transformation, Genetic