Location: Pest Management and Biocontrol ResearchTitle: A long non-coding RNA regulates cadherin transcription and susceptibility to Bt toxin Cry1Ac in pink bollworm, Pectinophora gossypiella
|LI, SHENGYUN - Nanjing Agricultural University|
|HUSSAIN, FIAZ - University Of Agriculture - Pakistan|
|UNNITHAN, GOPALAN - University Of Arizona|
|DONG, SHUANGLIN - Nanjing Agricultural University|
|ULABDIN, ZAIN - University Of Arizona|
|GU, SHAOHUA - Nanjing Agricultural University|
|CARRIERE, YVES - University Of Arizona|
|TABASHNIK, BRUCE - University Of Arizona|
|LI, XIANCHUN - University Of Arizona|
Submitted to: Pesticide Biochemistry and Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/17/2019
Publication Date: 4/19/2019
Publication URL: https://handle.nal.usda.gov/10113/6379083
Citation: Li, S., Hussain, F., Unnithan, G.C., Dong, S., Ulabdin, Z., Gu, S., Mathew, L.G., Fabrick, J.A., Ni, X., Carriere, Y., Tabashnik, B.E., Li, X. 2019. A long non-coding RNA regulates cadherin transcription and susceptibility to Bt toxin Cry1Ac in pink bollworm, Pectinophora gossypiella. Pesticide Biochemistry and Physiology. 158:54-60. https://doi.org/10.1016/j.pestbp.2019.04.007.
Interpretive Summary: The long-term, repetitive use of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) can lead to pest resistance and ultimately the loss of such important pest management tools. Resistance to Bt proteins are most commonly caused by direct gene mutations that disrupt the ability of the Bt protein to bind to its respective tissue and thereby prevents the toxin from effectively targeting the pest. Here, ARS researchers at Maricopa, AZ and Tifton, GA, with university collaborators discovered a new mechanism of how insecticide resistance to Bt crops is controlled. Namely, a pink bollworm cadherin gene responsible for Bt intoxication is inherently regulated by another RNA molecule produced from within the same cadherin gene. This RNA molecule, known as a long non-coding RNA, can regulate the expression of cadherin and when disrupted, leads to resistance to a Bt protein. Such lncRNA-mediated resistance represents a previously unknown mechanism for pest resistance to Bt crops.
Technical Abstract: Extensive planting of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has spurred increasingly rapid evolution of resistance in pests. In the pink bollworm, Pectinophora gossypiella, a devastating global pest, resistance to Bt toxin Cry1Ac produced by transgenic cotton is linked with mutations in a gene (PgCad1) encoding a cadherin protein that binds Cry1Ac in the larval midgut. We previously reported a long non-coding RNA (lncRNA) in intron 20 of cadherin alleles associated with both resistance and susceptibility to Cry1Ac. Here we tested the hypothesis that reducing expression of this lncRNA decreases transcription of PgCad1 and susceptibility to Cry1Ac. Quantitative RT-PCR showed that feeding susceptible neonates small interfering RNAs (siRNAs) targeting this lncRNA but not PgCad1 decreased the abundance of transcripts of both the lncRNA and PgCad1. Moreover, neonates fed the siRNAs had lower susceptibility to Cry1Ac. The results imply that the lncRNA increases transcription of PgCad1 and susceptibility of pink bollworm to Cry1Ac. The results suggest that disruption of lncRNA expression could be a novel mechanism of pest resistance to Bt toxins.