A cis-Acting Mutation in the PxABCG1 Promoter Is Associated with Cry1Ac Resistance in Plutella xylostella (L.)

The molecular mechanisms of insect resistance to Cry toxins generated from the bacterium Bacillus thuringiensis (Bt) urgently need be elucidated enable improvement and sustainability Bt-based products. Although downregulation expression midgut receptor genes is a pivotal mechanism Bt toxins, underlying transcriptional regulation these remains elusive. Herein, we unraveled regulatory ABC transporter gene PxABCG1 (also called Pxwhite), functional Cry1Ac toxin in Plutella xylostella. promoters Cry1Ac-susceptible Cry1Ac-resistant strains were cloned analyzed, they showed clear differences activity. Subsequently, dual-luciferase reporter assay, yeast one-hybrid (Y1H) RNA interference (RNAi) experiments demonstrated that cis-mutation binding site Hox transcription factor Antennapedia (Antp) decreased promoter activity resistant strain eliminated Antp, thereby enhancing P. xylostella toxin. These results advance our knowledge roles cis- trans-regulatory variations evolution resistance, contributing more complete understanding mechanism.