6 results about "Cry1Ac" patented technology

The invention relates to an in-situ binding method for evaluating binding of Bt toxin Cry1Ac and midgut epithelial cells of cotton bollworm larvae. The method comprises the following steps: incubating and culturing midgut tissues of larvae of lepidoptera pests and a Bt toxin-containing Sf-900 II cell culture solution, carrying out immunostaining, observing and photographing through a laser confocal microscope, and finally carrying out quantitative processing on a fluorescence image by utilizing ImageJ software so as to calculate an average unit area fluorescence signal value. And further evaluating the difference between the binding amounts of the midgut epithelial cells and the Bt toxins of the larvae of different strains. The method can intuitively and accurately observe and evaluate the binding condition of the Bt toxin and the midgut epithelial cells on the premise of retaining the original structure and physiological environment of the midgut tissue of the larvae, provides direct data support for Bt resistance research, assists in analyzing the pest Bt resistance mechanism, has important significance in formulating resistance early warning and treatment strategies, and has a wide application prospect. The method is suitable for the biotechnical fields of Bt toxin insecticidal mechanism research, lepidoptera pest drug resistance mechanism exploration and the like.

The invention provides three Cry1Ac modified toxin proteins with high insecticidal activity and application of the Cry1Ac modified toxin proteins, and relates to the field of genetic engineering and biological control. The amino acid sequences of the three modified proteins are sequentially shown as SEQ ID NO: 1, SEQ ID NO: 3 and SEQ ID NO: 5, and the amino acid sequences are sequentially shown as SEQ ID NO: 2, SEQ ID NO: 4 and SEQ ID NO: 6. The insect-resistant protein is a Cry1Ac toxin modified protein with improved insecticidal activity, which is screened from a Cry1Ac toxin key region saturation mutation library targeting Asiatic corn borer cadherin and ABC transporter, has higher insecticidal activity on lepidoptera pests, can be used for preventing and controlling agricultural pests and resisting the Bt resistance problem, and has important scientific and practical significance.

The present application relates to the technical field of pest control, in particular to a short peptide simulating a Cry1Ac protein anti-insect function epitope and application thereof. The present application takes a cotton bollworm middle intestine cadherin fragment (HaCad-TBR) as a target, and carries out screening on a phage display random 6-peptide library constructed by the laboratory, to obtain a 6-peptide LTETGK capable of combining with the cotton bollworm middle intestine cadherin, i.e. the 6-peptide has the effect of simulating a key anti-insect function epitope of the Cry1Ac protein, and a recombinant insecticidal protein C8CL2 having good insecticidal activity on the cotton bollworm can be obtained by replacing Loop2 of Domain II in the Cry1Ac. The present application expands the diversity of anti-insect materials of the Cry1Ac protein, and provides a potential alternative new material for preventing and controlling target pests, and can be used for the prevention and control of Lepidoptera pests, and provides technical support for the development of Lepidoptera pest control products.

The present invention relates to a chimeric insecticidal protein and a use thereof. The protein comprises domain I and domain II of Cry1Ac protein and domain III of Cry1Igg protein which are sequentially linked, and exhibits strong weight-inhibitory activity and lethal activity against various lepidopteran pests. The provided chimeric insecticidal protein broadens the insecticidal spectrum of the original protein, and also enhances toxicity against pests, effectively slowing the development of pest resistance in nature, and has good application prospects in agricultural production.

The present application relates to the technical field of pest control, in particular to a 7-peptide simulating a functional epitope of Cry1Ac protein and application thereof. The amino acid sequence of the 7-peptide is shown as SEQ ID NO. 1. The 7-peptide A42 capable of binding to HaCad-TBR is obtained by bio-panning of a Ph.D.-7 phage library (New England Biolabs) with HaCad-TBR as a target protein, and the 7-peptide A42 is used to replace part of the amino acids of Cry1Ac toxin to obtain a recombinant insecticidal protein A42D2L2 having good insecticidal activity against cotton bollworms. The present application enriches the Cry1Ac protein insect-resistant materials, provides a potential alternative new material for preventing and controlling target pests, and can be used for the prevention and control of pests in the order Lepidoptera, and provides technical support for the development of Lepidoptera pest control products.

The present invention provides modified Cry1Ac protein having enhanced toxicity towards resistant pink bollworm (PBW) species. Insertion of said specific, tightly binding gut peptides in Cry1Ac at one or more identified sites increases the retention of toxin in the PBW gut. resulting in solubilisation and pore formation leading to sepsis and larval death. The modified Bt toxin exhibits significant toxicity against resistant pink bollworm and thus can be used for generation of insect resistant transgenic plants.