title: Citrus tristeza virus-based RNAi in citrus plants induces gene silencing in Diaphorina citri, a phloem-sap sucking insect vector of citrus greening disease (Huanglongbing).
abstract: A transient expression vector based on Citrus tristeza virus (CTV) is unusually stable. Because of its stability it is being considered for use in the field to control Huanglongbing (HLB), which is caused by Candidatus Liberibacter asiaticus (CLas) and vectored by Asian citrus psyllid, Diaphorina citri. In the absence of effective control strategies for CLas, emphasis has been on control of D. citri. Coincident cohabitation in phloem tissue by CLas, D. citri and CTV was exploited to develop a novel method to mitigate HLB through RNA interference (RNAi). Since CTV has three RNA silencing suppressors, it was not known if CTV-based vector could induce RNAi in citrus. Yet, expression of sequences targeting citrus phytoene desaturase gene by CTV-RNAi resulted in photo-bleaching phenotype. CTV-RNAi vector, engineered with truncated abnormal wing disc (Awd) gene of D. citri, induced altered Awd expression when silencing triggers ingested by feeding D. citri nymphs. Decreased Awd in nymphs resulted in malformed-wing phenotype in adults and increased adult mortality. This impaired ability of D. citri to fly would potentially limit the successful vectoring of CLas bacteria between citrus trees in the grove. CTV-RNAi vector would be relevant for fast-track screening of candidate sequences for RNAi-mediated pest control.
authors.affiliation: Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850, USA.
authors.forename: Subhas
authors.initials: S
authors.lastname: Hajeri
authors.affiliation: Department of Entomology and Nematology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850, USA.
authors.forename: Nabil
authors.initials: N
authors.lastname: Killiny
authors.affiliation: Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850, USA.
authors.forename: Choaa
authors.initials: C
authors.lastname: El-Mohtar
authors.affiliation: Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850, USA.
authors.forename: William O
authors.initials: WO
authors.lastname: Dawson
authors.affiliation: Department of Plant Pathology, University of Florida, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850, USA. Electronic address: gowda@ufl.edu.
authors.forename: Siddarame
authors.initials: S
authors.lastname: Gowda
mesh_terms: D000818:Animals; D002957:Citrus / Q000235:genetics / Q000382:microbiology*; D017790:Closterovirus / Q000145:classification / Q000235:genetics*; D020868:Gene Silencing; D017344:Genes, Insect; D006430:Hemiptera / Q000235:genetics* / Q000502:physiology; D009758:Nymph / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics; D052585:Phloem / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics; D034622:RNA Interference; D012367:RNA, Viral / Q000235:genetics*; D012230:Rhizobiaceae / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D012367:RNA, Viral; D010088:Oxidoreductases; C022398:phytoene dehydrogenase
keywords: Asian citrus psyllid (ACP); Citrus tristeza virus; RNAi pest management; Virus-based plant mediated-RNAi; Virus-induced gene silencing (VIGS)