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Full-Text Articles in Life Sciences
Double-Stranded Rna Technology To Control Insect Pests: Current Status And Challenges, Olivier Christiaens, Steve Whyard, Ana M. Vélez, Guy Smagghe
Double-Stranded Rna Technology To Control Insect Pests: Current Status And Challenges, Olivier Christiaens, Steve Whyard, Ana M. Vélez, Guy Smagghe
Department of Entomology: Faculty Publications
Exploiting the RNA interference (RNAi) gene mechanism to silence essential genes in pest insects, leading to toxic effects, has surfaced as a promising new control strategy in the past decade. While the first commercial RNAi-based products are currently coming to market, the application against a wide range of insect species is still hindered by a number of challenges. In this review, we discuss the current status of these RNAi- based products and the different delivery strategies by which insects can be targeted by the RNAi-triggering double-stranded RNA (dsRNA) molecules. Furthermore, this review also addresses a number of physiological and cellular …
Sublethal Endpoints In Non-Target Organism Testing For Insect-Active Ge Crops, Andrew Roberts, Chad J. Boeckman, Marina Mühl, Jörg Romeis, John L. Teem, Fernando H. Valicente, Judith K. Brown, Steven L. Levine, Richard L. Melnick, Thais B. Rodrigues, Ana M. Vélez, Xuguo Zhou, Richard L. Hellmich, Martin G. Edwards
Sublethal Endpoints In Non-Target Organism Testing For Insect-Active Ge Crops, Andrew Roberts, Chad J. Boeckman, Marina Mühl, Jörg Romeis, John L. Teem, Fernando H. Valicente, Judith K. Brown, Steven L. Levine, Richard L. Melnick, Thais B. Rodrigues, Ana M. Vélez, Xuguo Zhou, Richard L. Hellmich, Martin G. Edwards
Department of Entomology: Faculty Publications
Historically, genetically engineered (GE) plants that have incorporated genes conferring insect protection have primarily used Cry proteins derived from Bacillus thuringiensis (Bt) to achieve their insecticidal phenotype. As a result, regulators have developed a level of familiarity and confidence in reviewing plants incorporating these insecticidal proteins. However, new technologies have been developed that produce GE plants that incorporate pest protection by triggering an RNA interference (RNAi) response or proteins other than Bt Cry proteins. These technologies have new modes of action. Although the overall assessment paradigm for GE plants is robust, there are ongoing discussions about the appropriate tests and …
Rnai Targeting Of Rootworm Troponin I Transcripts Confers Root Protection In Maize, Elane Fishilevich, Andrew J. Bowling, Meghan L. F. Frey, Po-Hao Wang, Wendy Lo, Murugesan Rangasamy, Sarah E. Worden, Heather E. Pence, Premchand Gandra, Shannon L. Whitlock, Greg Schulenberg, Eileen Knorr, Linda Tenbusch, Jamie R. Lutz, Stephen Novak, Ronda L. Hamm, Karl D. Schnelle, Andreas Vilcinskas, Kenneth E. Narva
Rnai Targeting Of Rootworm Troponin I Transcripts Confers Root Protection In Maize, Elane Fishilevich, Andrew J. Bowling, Meghan L. F. Frey, Po-Hao Wang, Wendy Lo, Murugesan Rangasamy, Sarah E. Worden, Heather E. Pence, Premchand Gandra, Shannon L. Whitlock, Greg Schulenberg, Eileen Knorr, Linda Tenbusch, Jamie R. Lutz, Stephen Novak, Ronda L. Hamm, Karl D. Schnelle, Andreas Vilcinskas, Kenneth E. Narva
Department of Entomology: Faculty Publications
Western corn rootworm, Diabrotica virgifera virgifera, is the major agronomically important pest of maize in the US Corn Belt. To augment the repertoire of the available dsRNA-based traits that control rootworm, we explored a potentially haplolethal gene target, wings up A (wupA), which encodes Troponin I. Troponin I, a component of the Troponin-Tropomyosin complex, is an inhibitory protein involved in muscle contraction. In situ hybridization showed that feeding on wupA-targeted dsRNAs caused systemic transcript knockdown in D. v. virgifera larvae. The knockdown of wupA transcript, and by extension Troponin I protein, led to deterioration of the …
Advances In Molecular Research On Bed Bugs (Hemiptera: Cimicidae), Sanjay Basnet, Shripat T. Kamble
Advances In Molecular Research On Bed Bugs (Hemiptera: Cimicidae), Sanjay Basnet, Shripat T. Kamble
Department of Entomology: Faculty Publications
With the resurgence and increase in infestations of the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), across the world, there has been renewed interest in molecular research on this pest. In this paper, we present current information on the biology, medical importance, management practices, behavior and physiology, and molecular research conducted on bed bugs. The majority of molecular studies are focused towards understanding the molecular mechanism of insecticide resistance. Bed bugs are hematophagous insects with no prior record of vectoring any disease organisms. An improved understanding of how bed bugs lack vector competency may provide information to prevent disease …
Knockdown Of The Chromatin Remodeling Gene Brahma By Rna Interference Reduces Reproductive Fitness And Lifespan In Common Bed Bug (Hemiptera: Cimicidae), Sanjay Basnet, Shripat T. Kamble
Knockdown Of The Chromatin Remodeling Gene Brahma By Rna Interference Reduces Reproductive Fitness And Lifespan In Common Bed Bug (Hemiptera: Cimicidae), Sanjay Basnet, Shripat T. Kamble
Department of Entomology: Faculty Publications
The common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae) is a nuisance household pest causing significant medical and economic impacts. RNA interference (RNAi) of genes that are involved in vital physiological processes can serve as potential RNAi targets for insect control. Brahma is an ATPase subunit of a chromatin-remodeling complex involved in transcription of several genes for cellular processes, most importantly the homeotic genes. In this study, we used a microinjection technique to deliver double stranded RNA into female bed bugs. Delivery of 0.05 and 0.5 μg/insect of brahma dsRNA directly into hemocele resulted substantial reduction in oviposition. Eggs laid …
Rna Interference Of The Muscle Actin Gene In Bed Bugs: Exploring Injection Versus Topical Application For Dsrna Delivery, Sanjay Basnet, Shripat T. Kamble
Rna Interference Of The Muscle Actin Gene In Bed Bugs: Exploring Injection Versus Topical Application For Dsrna Delivery, Sanjay Basnet, Shripat T. Kamble
Department of Entomology: Faculty Publications
Bed bugs are one the most troublesome household pests that feed primarily on human blood. RNA interference (RNAi) is currently being pursued as a potential tool for insect population management and has shown efficacy against some phytophagous insects. We evaluated the different techniques to deliver dsRNA specific to bed bug muscle actin (dsactin) into bed bugs. Initially, stability of dsRNA in human blood was studied to evaluate the feasibility of feeding method. Adult bed bugs were injected with dsRNA between last thoracic segment and first abdominal segment on the ventral side, with a dose of 0.2 μg dsactin …
Improved Insect-Proofing: Expressing Double-Stranded Rna In Chloroplasts, Julia Bally, Elane Fishilevich, Andrew J. Bowling, Heather E. Pence, Kenneth E. Narva, Peter M. Waterhouse
Improved Insect-Proofing: Expressing Double-Stranded Rna In Chloroplasts, Julia Bally, Elane Fishilevich, Andrew J. Bowling, Heather E. Pence, Kenneth E. Narva, Peter M. Waterhouse
Department of Entomology: Faculty Publications
RNA interference (RNAi) was discovered almost 20 years ago and has been exploited worldwide to silence genes in plants and animals. A decade later, it was found that transforming plants with an RNAi construct targeting an insect gene could protect the plant against feeding by that insect. Production of double-stranded RNA (dsRNA) in a plant to affect the viability of a herbivorous animal is termed trans-kingdom RNAi (TK-RNAi). Since this pioneering work, there have been many further examples of successful TK-RNAi, but also reports of failed attempts and unrepeatable experiments. Recently, three laboratories have shown that producing dsRNA in a …
Knockdown Of Rna Interference Pathway Genes In Western Corn Rootworm, Diabrotica Virgifera Virgifera, Identifies No Fitness Costs Associated With Argonaute 2 Or Dicer-2, Carolina Camargo, Ke Wu, Elane Fishilevich, Kenneth E. Narva, Blair Siegfried
Knockdown Of Rna Interference Pathway Genes In Western Corn Rootworm, Diabrotica Virgifera Virgifera, Identifies No Fitness Costs Associated With Argonaute 2 Or Dicer-2, Carolina Camargo, Ke Wu, Elane Fishilevich, Kenneth E. Narva, Blair Siegfried
Department of Entomology: Faculty Publications
The use of transgenic crops that induce silencing of essential genes using double-stranded RNA (dsRNA) through RNA interference (RNAi) in western corn rootworm, Diabrotica virgifera virgifera, is likely to be an important component of new technologies for the control of this important corn pest. Previous studies have demonstrated that the dsRNA response in D. v. virgifera depends on the presence of RNAi pathway genes including Dicer-2 and Argonaute 2, and that down-regulation of these genes limits the lethality of environmental dsRNA. A potential resistance mechanism to lethal dsRNA may involve loss of function of RNAi pathway genes. However, …
Rnai Induced Knockdown Of A Cadherin-Like Protein (Ef531715) Does Not Affect Toxicity Of Cry34/35ab1 Or Cry3aa To Diabrotica Virgifera Virgifera Larvae (Coleoptera: Chrysomelidae), Sek Yee Tan, Murugesan Rangasamy, Haichuan Wang, Ana Maria Vélez, James Hasler, David Mccaskill, Tao Xu, Hong Chen, Jessica Jurzenski, Matthew Kelker, Xiaoping Xu, Kenneth E. Narva, Blair D. Siegfried
Rnai Induced Knockdown Of A Cadherin-Like Protein (Ef531715) Does Not Affect Toxicity Of Cry34/35ab1 Or Cry3aa To Diabrotica Virgifera Virgifera Larvae (Coleoptera: Chrysomelidae), Sek Yee Tan, Murugesan Rangasamy, Haichuan Wang, Ana Maria Vélez, James Hasler, David Mccaskill, Tao Xu, Hong Chen, Jessica Jurzenski, Matthew Kelker, Xiaoping Xu, Kenneth E. Narva, Blair D. Siegfried
Department of Entomology: Faculty Publications
The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is an important maize pest throughout most of the U.S. Corn Belt. Bacillus thuringiensis (Bt) insecticidal proteins including modified Cry3Aa and Cry34/35Ab1 have been expressed in transgenic maize to protect against WCR feeding damage. To date, there is limited information regarding the WCR midgut target sites for these proteins. In this study, we examined whether a cadherin-like gene from Diabrotica virgifera virgifera (DvvCad; Gen-Bank accession # EF531715) associated with WCR larval midgut tissue is necessary for Cry3Aa or Cry34/ 35Ab1 toxicity. Experiments were designed to examine the sensitivity of WCR to …
Rnai As A Management Tool For The Western Corn Rootworm, Diabrotica Virgifera Virgifera, Elane Fishilevich, Ana Maria Vélez, Nicholas P. Storer, Huarong Li, Andrew J. Bowling, Murugesan Rangasamy, Sarah E. Worden, Kenneth E. Narva, Blair D. Siegfried
Rnai As A Management Tool For The Western Corn Rootworm, Diabrotica Virgifera Virgifera, Elane Fishilevich, Ana Maria Vélez, Nicholas P. Storer, Huarong Li, Andrew J. Bowling, Murugesan Rangasamy, Sarah E. Worden, Kenneth E. Narva, Blair D. Siegfried
Department of Entomology: Faculty Publications
The western corn rootworm (WCR), Diabrotica virgifera virgifera, is the most important pest of corn in the US Corn Belt. Economic estimates indicate that costs of control and yield loss associated with WCR damage exceed $US 1 billion annually. Historically, corn rootworm management has been extremely difficult because of its ability to evolve resistance to both chemical insecticides and cultural control practices. Since 2003, the only novel commercialized developments in rootworm management have been transgenic plants expressing Bt insecticidal proteins. Four transgenic insecticidal proteins are currently registered for rootworm management, and field resistance to proteins from the Cry3 family …
Parental Rna Interference Of Genes Involved In Embryonic Development Of The Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Chitvan Khajuria, Ana María Vélez, Murugesan Rangasamy, Haichuan Wang, Elane Fishilevich, Meghan L.F. Frey, Newton Portilho Carneiro, Premchand Gandra, Kenneth E. Narva, Blair D. Siegfried
Parental Rna Interference Of Genes Involved In Embryonic Development Of The Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Chitvan Khajuria, Ana María Vélez, Murugesan Rangasamy, Haichuan Wang, Elane Fishilevich, Meghan L.F. Frey, Newton Portilho Carneiro, Premchand Gandra, Kenneth E. Narva, Blair D. Siegfried
Department of Entomology: Faculty Publications
RNA interference (RNAi) is being developed as a potential tool for insect pest management and one of the most likely target pest species for transgenic plants that express double stranded RNA (dsRNA) is the western corn rootworm. Thus far, most genes proposed as targets for RNAi in rootworm cause lethality in the larval stage. In this study, we describe RNAi mediated knockdown of two developmental genes, hunchback (hb) and brahma (brm), in the western corn rootworm delivered via dsRNA fed to adult females. dsRNA feeding caused a significant decrease in hb and brm transcripts in the adult females. Although …