Bt
not annotated - annotated - LINNAEUS only
21815956
Insertion of an intact CR1 retrotransposon in a cadherin gene linked with Bt resistance in the pink bollworm, Pectinophora gossypiella.
Three mutations in the Pectinophora gossypiella cadherin gene PgCad1 are linked with resistance to Bacillus thuringiensis (Bt) toxin Cry1Ac. Here we show that the r3 mutation entails recent insertion into PgCad1 of an active chicken repeat (CR1) retrotransposon, designated CR1-1_Pg. Unlike most other CR1 elements, CR1-1_Pg is intact, transcribed by a flanking promoter, contains target site duplications and has a relatively low number of copies. Examination of transcripts from the PgCad1 locus revealed that CR1-1_Pg disrupts both the cadherin protein and a long noncoding RNA of unknown function. Together with previously reported data, these findings show that transposable elements disrupt eight of 12 cadherin alleles linked with resistance to Cry1Ac in three lepidopteran species, indicating that the cadherin locus is a common target for disruption by transposable elements.
21205278
Molecular characterization of three genes encoding aminopeptidases N in the poplar leaf beetle Chrysomela tremulae.
Three genes encoding proteins showing sequence similarity and features typical of insect APNs were characterized in C. tremulae and designed as CtAPN1, CtAPN2 and CtAPN3. Expression analysis of the three C. tremulae APN genes showed that CtAPN2 transcript is more abundant in the fat body, whereas both CtAPN1 and CtAPN3 are specifically expressed in the midgut. Despite a similar genomic organization, lepidopteran and coleopteran APNs are phylogenetically distant, suggesting that APN gene duplication events occurred after these two insect orders split. Sequence and expression comparisons of CtAPN1, CtAPN2 and CtAPN3 cDNAs in a C. tremulae Bacillus thuringiensis (Bt)-susceptible and in a Bt-resistant strain did not show any polymorphism at the amino acid level or difference at the transcription level.