title: Genetically modifying the insect gut microbiota to control Chagas disease vectors through systemic RNAi.
abstract: Technologies based on RNA interference may be used for insect control. Sustainable strategies are needed to control vectors of Chagas disease such as Rhodnius prolixus. The insect microbiota can be modified to deliver molecules to the gut. Here, Escherichia coli HT115(DE3) expressing dsRNA for the Rhodnius heme-binding protein (RHBP) and for catalase (CAT) were fed to nymphs and adult triatomine stages. RHBP is an egg protein and CAT is an antioxidant enzyme expressed in all tissues by all developmental stages. The RNA interference effect was systemic and temporal. Concentrations of E. coli HT115(DE3) above 3.35 × 10(7) CFU/mL produced a significant RHBP and CAT gene knockdown in nymphs and adults. RHBP expression in the fat body was reduced by 99% three days after feeding, returning to normal levels 10 days after feeding. CAT expression was reduced by 99% and 96% in the ovary and the posterior midgut, respectively, five days after ingestion. Mortality rates increased by 24-30% in first instars fed RHBP and CAT bacteria. Molting rates were reduced by 100% in first instars and 80% in third instars fed bacteria producing RHBP or CAT dsRNA. Oviposition was reduced by 43% (RHBP) and 84% (CAT). Embryogenesis was arrested in 16% (RHBP) and 20% (CAT) of laid eggs. Feeding females 105 CFU/mL of the natural symbiont, Rhodococcus rhodnii, transformed to express RHBP-specific hairpin RNA reduced RHBP expression by 89% and reduced oviposition. Modifying the insect microbiota to induce systemic RNAi in R. prolixus may result in a paratransgenic strategy for sustainable vector control.
authors: Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundão, Rio de Janeiro, Brasil; eCentro de Estudios en Salud. Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors: Mabel L
authors: ML
authors: Taracena
authors: Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundão, Rio de Janeiro, Brasil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Brasil.
authors: Pedro L
authors: PL
authors: Oliveira
authors: Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Atlanta, Georgia, United States of America.
authors: Olivia
authors: O
authors: Almendares
authors: eCentro de Estudios en Salud. Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors: Claudia
authors: C
authors: Umaña
authors: Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
authors: Carl
authors: C
authors: Lowenberger
authors: Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Atlanta, Georgia, United States of America.
authors: Ellen M
authors: EM
authors: Dotson
authors: Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundão, Rio de Janeiro, Brasil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Brasil.
authors: Gabriela O
authors: GO
authors: Paiva-Silva
authors: Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
authors: Pamela M
authors: PM
authors: Pennington
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics; D002374:Catalase / Q000235:genetics; D014355:Chagas Disease / Q000517:prevention & control*; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D000069196:Gastrointestinal Microbiome / Q000235:genetics*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D055785:Gene Knockdown Techniques; D005822:Genetic Vectors; D006418:Heme / Q000378:metabolism; D000081062:Heme-Binding Proteins; D006420:Hemeproteins / Q000235:genetics; D007300:Insect Control / Q000379:methods*; D007303:Insect Vectors / Q000382:microbiology*; D034622:RNA Interference; D012330:RNA, Double-Stranded; D034741:RNA, Small Interfering / Q000235:genetics; D012239:Rhodnius / Q000382:microbiology*; D014349:Trypanosoma cruzi / Q000472:pathogenicity
chemical_list: D002352:Carrier Proteins; D000081062:Heme-Binding Proteins; D006420:Hemeproteins; D012330:RNA, Double-Stranded; D034741:RNA, Small Interfering; D006418:Heme; D002374:Catalase