|MALIK, HASSAN - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|RAZA, AMIR - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|AMIN, IMRAN - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
|BROWN, JUDITH - University Of Arizona|
|MANSOOR, SHAHID - National Institute Of Biotechnology And Genetic Engineering (NIBGE)|
Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/10/2016
Publication Date: 12/8/2016
Citation: Malik, H.J., Raza, A., Amin, I., Scheffler, J.A., Scheffler, B.E., Brown, J.K., Mansoor, S. 2016. RNAi-mediated mortality of the whitefly through transgenic expression of double-stranded RNA homologous to acetylcholinesterase and ecdysone receptor in tobacco plants. Scientific Reports. 6. doi:10.1038/srep38469.
Interpretive Summary: Cotton leaf curl virus is a devastating disease in Pakistan and is spreading to other countries. Millions of bales of cotton are lost each year due to this virus and there are currently no resistant varieties available. It may be possible to decrease the spread of the virus using new biotechnology methods. Here modified forms of two whitefly genes were inserted into a cotton plant. The genes work by producing a special type of RNA that specifically targets and downregulates the whitefly acetylcholinesterase (AChE) gene and the ecdysone receptor (EcR) gene. When acetylcholinesterase is inactivated it causes paralysis and death of the whitefly. Low expression of the ecdysone receptor gene inhibits reproduction and the whiteflies ability to tolerate stress. In this study, feeding on the genetically modified plants, caused rapid whitefly mortality and decreased the number of whitefly that could reproduce. This new technological approach can complement traditional methods of insect control and give the plant breeder more techniques to use in mitigating the effects of cotton leaf curl virus disease.
Technical Abstract: The whitefly Bemisia tabaci (Genn.) is a pest and vector of plant viruses affecting plants worldwide. Using RNA interference (RNAi) to downregulate whitefly genes by expressing their homologous double stranded RNAs in plants has great potential for management of whiteflies to reduce plant virus disease spread. Using a Tobacco rattle virus-derived plasmid for in planta transient expression of double stranded RNA (dsRNA) homologous to the acetylcholinesterase (AChE) and ecdysone receptor (EcR) genes of B. tabaci, resulted in significant adult whitefly mortality. Nicotiana tabacum L. plants expressing dsRNA homologous to B. tabaci AChE and EcR were constructed by fusing sequences derived from both genes. Mortality of adult whiteflies exposed to dsRNA by feeding on N. tabacum plants, compared to non-dsRNA expressing plants, recorded at 24-hr intervals post-ingestion for three days, was >90% and 10%, respectively. Analysis of gene expression by real time quantitative PCR indicated that whitefly mortality was attributable to the down-regulation of both target genes by RNAi. Results indicated that knock down of whitefly genes involved in neuronal transmission and transcriptional activation of developmental genes, has potential as a bio-pesticide to reduce whitefly population size and thereby decrease virus spread.