Toggle Main Menu Toggle Search

Open Access padlockePrints

Downregulation and Mutation of a Cadherin Gene Associated with Cry1Ac Resistance in the Asian Corn Borer, Ostrinia furnacalis (Guenée)

Lookup NU author(s): Professor Angharad MR Gatehouse, Dr Martin Edwards

Downloads


Licence

This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Abstract

Development of resistance in target pests is a major threat to long-term use of transgenic crops expressing Bacillus thuringiensis (Bt) Cry toxins. To manage and/or delay the evolution of resistance in target insects through the implementation of effective strategies, it is essential to understand the basis of resistance. One of the most important mechanisms of insect resistance to Bt crops is the alteration of the interactions between Cry toxins and their receptors in the midgut. A Cry1Ac-selected strain of Asian corn borer (ACB), Ostrinia furnacalis, a key pest of maize in China, evolved three mutant alleles of a cadherin-like protein (OfCAD) (MPR-r1, MPR-r2 and MPR-r3), which mapped within the toxin-binding region (TBR). Each of the three mutant alleles possessed two or three amino acid substitutions in this region, especially Thr(1457)-> Ser. In highly resistant larvae (ACB-Ac200), MPR-r2 had a 26-amino acid residue deletion in the TBR, which resulted in reduced binding of Cry1Ac compared to the MPR from the susceptible strain, suggesting that the number of amino acid deletions influences the level of resistance. Furthermore, downregulation of OfCAD gene (ofcad) transcription was observed in the Cry1Ac resistant strain, ACB-Ac24, suggesting that Cry1Ac resistance in ACB is associated with the downregulation of the transcript levels of the cadherin-like protein gene. The OfCAD identified from ACB exhibited a high degree of similarity to other members of the cadherin super-family in lepidopteran species.


Publication metadata

Author(s): Jin TT, Chang X, Gatehouse AMR, Wang ZY, Edwards MG, He KL

Publication type: Article

Publication status: Published

Journal: Toxins

Year: 2014

Volume: 6

Issue: 9

Pages: 2676-2693

Online publication date: 11/09/2014

Acceptance date: 15/08/2014

Date deposited: 01/12/2014

ISSN (electronic): 2072-6651

Publisher: MDPI AG

URL: http://dx.doi.org/10.3390/toxins6092676

DOI: 10.3390/toxins6092676


Altmetrics

Altmetrics provided by Altmetric


Actions

Find at Newcastle University icon    Link to this publication


Share