title: Cucumber mosaic virus and its 2b RNA silencing suppressor modify plant-aphid interactions in tobacco.
abstract: The cucumber mosaic virus (CMV) 2b protein not only inhibits anti-viral RNA silencing but also quenches transcriptional responses of plant genes to jasmonic acid, a key signalling molecule in defence against insects. This suggested that it might affect interactions between infected plants and aphids, insects that transmit CMV. We found that infection of tobacco with a 2b gene deletion mutant (CMVΔ2b) induced strong resistance to aphids (Myzus persicae) while CMV infection fostered aphid survival. Using electrical penetration graph methodology we found that higher proportions of aphids showed sustained phloem ingestion on CMV-infected plants than on CMVΔ2b-infected or mock-inoculated plants although this did not increase the rate of growth of individual aphids. This indicates that while CMV infection or certain viral gene products might elicit aphid resistance, the 2b protein normally counteracts this during a wild-type CMV infection. Our findings suggest that the 2b protein could indirectly affect aphid-mediated virus transmission.
authors.affiliation: University of Cambridge, Department of Plant Sciences, Downing Street, Cambridge, CB2 3EA, UK.
authors.forename: Heiko
authors.initials: H
authors.lastname: Ziebell
authors.forename: Alex M
authors.initials: AM
authors.lastname: Murphy
authors.forename: Simon C
authors.initials: SC
authors.lastname: Groen
authors.forename: Trisna
authors.initials: T
authors.lastname: Tungadi
authors.forename: Jack H
authors.initials: JH
authors.lastname: Westwood
authors.forename: Mathew G
authors.initials: MG
authors.lastname: Lewsey
authors.forename: Michael
authors.initials: M
authors.lastname: Moulin
authors.forename: Adam
authors.initials: A
authors.lastname: Kleczkowski
authors.forename: Alison G
authors.initials: AG
authors.lastname: Smith
authors.forename: Mark
authors.initials: M
authors.lastname: Stevens
authors.forename: Glen
authors.initials: G
authors.lastname: Powell
authors.forename: John P
authors.initials: JP
authors.lastname: Carr
mesh_terms: D000818:Animals; D001042:Aphids / Q000502:physiology*; D001522:Behavior, Animal; D017799:Cucumovirus / Q000235:genetics* / Q000502:physiology; D003517:Cyclopentanes / Q000378:metabolism; D005247:Feeding Behavior; D017353:Gene Deletion; D020868:Gene Silencing; D009154:Mutation; D009538:Nicotine / Q000378:metabolism; D054883:Oxylipins / Q000378:metabolism; D052585:Phloem / Q000378:metabolism; D010935:Plant Diseases; D034741:RNA, Small Interfering / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics* / Q000821:virology; D014764:Viral Proteins / Q000235:genetics* / Q000502:physiology
chemical_list: C404227:2b protein, cucumber mosaic virus; D003517:Cyclopentanes; D054883:Oxylipins; D034741:RNA, Small Interfering; D014764:Viral Proteins; D009538:Nicotine; C011006:jasmonic acid