title: Construction of plant vectors with high level expression of B.t. toxin gene and studies on their expression behavior in transgenic tobaccos.
abstract: Breeding pest-resistant plants using plant genetic engineering technique is an effective strategy in integrated pest management (IPM). Increasing the expression level of foreign insecticidal protein by using a strong promoter is a useful method. In this work, a plant expression vector, pBinMoBc, was constructed. It contained the CryIA(c) gene under the control of a chimeric OM promoter and the omega factor. As a control, another vector, pBinoBc, was also constructed in this study. pBinoBc carrying CryIA(c) gene was under the control of a CaMV 35S promoter. The vectors were transferred into tobacco plants via Agrobacterium-mediated transformation. ELISA assay showed that the average expression level of the CryIA(c) gene in pBinMoBc transgenic tobacco plants is 2.44-times that in pBinoBc transgenic tobacco plants. The expression of B.t. toxin in individual plant can be up to 0.255% of total soluble proteins. Bioassay showed that pBinMoBc transgenic tobacco plants had more notable insecticidal effects than pBinoBc transgenic tobacco plants. The above results showed that the chimeric OM promoter is a stronger promoter than the CaMV 35S promoter that was widely used in plant genetic engineering. This is very useful in pest-resistant plant genetic engineering.
authors.affiliation: Institute of Genetics, The Chinese Academy of Sciences, Beijing.
authors.forename: S
authors.initials: S
authors.lastname: Chunlin
authors.forename: Z
authors.initials: Z
authors.lastname: Zhen
authors.forename: X
authors.initials: X
authors.lastname: Guifang
authors.forename: I
authors.initials: I
authors.lastname: Altosaar
authors.forename: F
authors.initials: F
authors.lastname: Pingzhang
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000096:biosynthesis*; D001427:Bacterial Toxins / Q000096:biosynthesis*; D001681:Biological Assay; D004731:Endotoxins / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D005822:Genetic Vectors; D006460:Hemolysin Proteins; D007306:Insecticides / Q000378:metabolism*; D007814:Larva; D009036:Moths; D010572:Pest Control, Biological; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D016133:Polymerase Chain Reaction; D014026:Nicotiana / Q000235:genetics
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis