Submitted to: Nature Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/17/2000
Publication Date: 6/1/2000
Citation: Kramer, K.J., Morgan, T.D., Throne, J.E., Dowell, F.E., Bailey, M., Howard, J.A. 2000. Transgenic avidin maize is resistant to storage insect pests. Nature Biotechnology. 18(6): 670-674. Interpretive Summary: This paper describes a potentially very useful biotechnology for controlling stored product insect pests. Results of collaborative research with ProdiGene, Inc. (College Station, TX) demonstrate that a new type of transgenic corn (maize) is insect-resistant. This corn contains the protein avidin which results in kernels that have resistance to many stored product insects because avidin binds the essential vitamin biotin.Insects feeding on this corn develop a biotin deficiency that leads to delayed development and toxicity. Avidin is a rather unique biopesticide because it is a protein found in one of nature's most nutritious creations, the chicken egg. Avidin occurs in the transgenic grain at only a fraction of the level present in eggs. This is one of the very few new ideas for use of transgenic plant biotechnology for insect pest management and has exciting possibilities.
Technical Abstract: Transgenic avidin maize is resistant to insect pests that damage grains during storage. When present in seeds at levels greater than 100 ppm, avidin prevents development or is toxic to many internal and external feeding pests including Sitophilus zeamais, Rhyzopertha dominica, Sitotroga cerealella, Trogoderma variabile, Oryzaephilus surinamensis, Cryptolestes pusillus, Tribolium castaneum, T. confusum, Plodia interpunctella, and Anagasta kuehniella. One species, Prostephanus truncatus, however, is tolerant of the protein. Avidin is a food protein found in chicken egg white. It is a biopesticide because it sequesters the vitamin biotin, but its adverse effects can be prevented by denaturation or supplementation with the vitamin. Avidin maize is not acutely toxic to mice when administered as the sole component of their diet. Automated near infrared spectroscopy can be used to distinguish high avidin (insect resistant) kernels from low avidin kernels. Avidin has good potential for use as a biopesticide in transgenic plants to control both pre- and post-harvest insect pests.