Sequence variation in the cadherin gene of Ostrinia nubilalis:: a tool for field monitoring

Toxin-binding proteins of insect midgut epithelial cells are associated with insect resistance to Bacillus thuringiensis (Bt) Cry toxins. A 5378 nt cDNA encoding a 1717 amino acid putative midgut cadherin-like glycoprotein and candidate CrylAb toxin-binding protein was characterized front Ostrinia nubilalis. Intraspecific alignment of partial O. nubilalis cadherin gene sequences identified variance within proposed CrylA toxin binding region 2 (TBR2), (1328)IPLQTSILVVT[I/V] N-1340, and flanking CrylA toxin binding region 1 (TBR1). (DIEIEIIDTNN871)-D-861. DNA sequence and PCR-RFLP detected single nucleotide polymorphism between cadherin alleles. and pedigree analysis demonstrated Mendelian inheritance. A population sample from Mead. Nebraska showed allelic polyrnorphism. These assays may be useful for linkage mapping and field surveillance of wild Populations and of O. nubilalis. Published by Elsevier Ltd.