Author
Isabel Gómez
Bio: Isabel Gómez is an academic researcher from National Autonomous University of Mexico. The author has contributed to research in topics: Bacillus thuringiensis & Cadherin. The author has an hindex of 28, co-authored 71 publications receiving 3890 citations.
Papers published on a yearly basis
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Swedish University of Agricultural Sciences1, Commonwealth Scientific and Industrial Research Organisation2, University of Exeter3, University of Bath4, George Washington University5, Ghent University6, Centre for DNA Fingerprinting and Diagnostics7, University of Copenhagen8, Kansas State University9, University of Montpellier10, Max Planck Society11, University of Warsaw12, University of Georgia13, National Autonomous University of Mexico14, Australian National University15, University of Valencia16, Wageningen University and Research Centre17, Agriculture and Agri-Food Canada18, University of Saskatchewan19, Stockholm University20, Eötvös Loránd University21, University of Tokyo22, National Institute of Advanced Industrial Science and Technology23, Plant & Food Research24, Oregon State University25, Agricultural Research Service26, Leiden University27, University of Manitoba28
TL;DR: Despite a large variation in the data, trends that are found are that RNAi is particularly successful in the family Saturniidae and in genes involved in immunity and that gene expression in epidermal tissues seems to be most difficult to silence.
698 citations
TL;DR: The data suggest that the two receptors of Cry1Ab toxin interact sequentially with different structural species of the toxin leading to its efficient membrane insertion.
415 citations
TL;DR: A model where receptor binding allows the efficient cleavage of α‐1 and formation of a pre‐pore oligomeric structure that is efficient in pore formation, is presented.
264 citations
TL;DR: It is suggested that cadherin promotes Bt toxicity by facilitating toxin oligomerization and it is demonstrated that the modified Bt toxins may be useful against pests resistant to standard BT toxins.
Abstract: The evolution of insect resistance threatens the effectiveness of Bacillus thuringiensis (Bt) toxins that are widely used in sprays and transgenic crops. Resistance to Bt toxins in some insects is linked with mutations that disrupt a toxin-binding cadherin protein. We show that susceptibility to the Bt toxin Cry1Ab was reduced by cadherin gene silencing with RNA interference in Manduca sexta, confirming cadherin's role in Bt toxicity. Native Cry1A toxins required cadherin to form oligomers, but modified Cry1A toxins lacking one alpha-helix did not. The modified toxins killed cadherin-silenced M. sexta and Bt-resistant Pectinophora gossypiella that had cadherin deletion mutations. Our findings suggest that cadherin promotes Bt toxicity by facilitating toxin oligomerization and demonstrate that the modified Bt toxins may be useful against pests resistant to standard Bt toxins.
262 citations
TL;DR: It is believed that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate‐limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improved of mutagenesis strategies and selection procedures.
Abstract: Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificity. In this review we discuss how Cry toxins have evolved insect specificity in nature and analyse several cases of improvement of Cry toxin action by genetic engineering, some of these examples are currently used in transgenic crops. We believe that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate-limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improvement of mutagenesis strategies and selection procedures.
221 citations
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TL;DR: Recent evidence suggests that Cyt synergize or overcome resistance to mosquitocidal-Cry proteins by functioning as a Cry-membrane bound receptor, and compares them to the mode of action of other bacterial PFT.
1,171 citations
1,147 citations
TL;DR: Current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance is presented.
926 citations
TL;DR: Recently, similar Cry-binding proteins have been identified in the three insect orders, as cadherin, aminopeptidase-N and alkaline phosphatase suggesting a conserved mode of action, suggesting a significant reduction in chemical insecticide use.
885 citations
TL;DR: Analysis of more than a decade of global monitoring data reveals that the frequency of resistance alleles has increased substantially in some field populations of Helicoverpa zea, but not in five other major pests in Australia, China, Spain and the United States.
Abstract: Evolution of insect resistance threatens the continued success of transgenic crops producing Bacillus thuringiensis (Bt) toxins that kill pests. The approach used most widely to delay insect resistance to Bt crops is the refuge strategy, which requires refuges of host plants without Bt toxins near Bt crops to promote survival of susceptible pests. However, large-scale tests of the refuge strategy have been problematic. Analysis of more than a decade of global monitoring data reveals that the frequency of resistance alleles has increased substantially in some field populations of Helicoverpa zea, but not in five other major pests in Australia, China, Spain and the United States. The resistance of H. zea to Bt toxin Cry1Ac in transgenic cotton has not caused widespread crop failures, in part because other tactics augment control of this pest. The field outcomes documented with monitoring data are consistent with the theory underlying the refuge strategy, suggesting that refuges have helped to delay resistance.
727 citations