Genetic knockout of the BtR4 gene encoding the Heliothis virescens cadherin-like protein (HevCaLP) is linked to resistance against Cry1Ac toxin from Bacillus thuringiensis. However, the functional Cry1Ac receptor role of this protein has not been established. We previously proposed HevCaLP as a shared binding site for B. thuringiensis (Bt) Cry1A and Cry1Fa toxins in the midgut epithelium of H. ...

We determined that Bacillus thuringiensis Cry1Ac and Cry1Fa delta-endotoxins recognize the same 110, 120 and 170 kDa aminopeptidase N (APN) molecules in brush border membrane vesicles (BBMV) from Heliothis virescens. The 110 kDa protein, not previously identified as an APN, contained a variant APN consensus sequence identical to that found in Helicoverpa punctigera APN 2. PCR amplification of H...

In summer 2000, adult female bollworm moths, Helicoverpa zea (Boddie), were collected from light-traps at four locations near the Tidewater Research Station, Plymouth, NC. Female moths were allowed to lay eggs, and at hatch, 72 larvae from each female were screened for growth rate on normal artificial diet and on diets containing 5.0 microg of either Cry1Ac or Cry2Aa Bt toxin per milliliter of ...

Malaria is a major global health problem that kills 1-2 million people each year. Despite exhaustive research, naturally acquired immunity is poorly understood. Cry1A proteins are potent immunogens with adjuvant properties and are able to induce strong cellular and humoral responses. In fact, it has been shown that administration of Cry1Ac protoxin alone or with amoebic lysates induces protecti...

Bacillus thuringiensis (Bt) produces Cry toxins against pest insects. proteins are conformed by domains related to pore formation and recognition of protein receptors. Plant-induced systemic resistance (ISR) is triggered due attack, it could be activated sp. Tecia solanivora (Ts) a potato pest, susceptible Cry1Ac Cry1B proteins. This paper indicates the endorsement Bt kurstaki HD-1 (BtkHD1) in ...

Transgenic corn and cotton expressing Cry and/or Vip3Aa proteins from Bacillus thuringiensis (Bt) have been planted for managing lepidopteran coleopteran insect pests more than two decades in the U.S. Evolution of resistance to these Bt is a major threat continued efficacy technology. Understanding patterns cross-resistance dominance target insects essential management pest control. The bollwor...

Transgenic Bt-cotton expresses insecticidal Cry proteins via Cry genes, introduced from the soil bacterium Bacillus thuringiensis (Bt). Data on levels of Cry proteins expressed in transgenic Bt-crops is important for assessing levels of environmental exposure. During investigations into the rhizosphere impacts of Cry proteins from GM cotton we found that Cry1Ac expression throughout the season ...

The Old World bollworm, Helicoverpa armigera (Hübner), was recently introduced into Brazil, where it has caused extensive damage to cotton and soybean crops. MON 87701 × MON 89788 soybean, which expresses the Bt protein Cry1Ac, was recently deployed in Brazil, providing high levels of control against H. armigera. To assess the risk of resistance to the Cry1Ac protein expressed by MON 87701 × MO...

BACKGROUND Bt-cry1Ac gene has been reputedly effective against Helicoverpa armigera a notorious lepidopteran pest. Reports on the expression of full-length and truncated cry1Ac genes in plants for effective resistance against Helicoverpa sp. have been documented however, their performance is still ambiguous. Moreover, the question remains to be addressed that truncation of 3' end of the native ...

Collards (Brassica oleracea var. acephala) are an important vegetable crucifer produced worldwide for human consumption, and one subject to severe injury by Lepidoptera. We have produced Bacillus thuringiensis (Bt)-transgenic collard lines that have the potential to be used either for direct control or as a ‘‘dead end’’ trap crop for Lepidoptera. To produce collard lines expressing Bt genes, a ...