title: Uncoating Mechanism of Carnation Mottle Virus Revealed by Cryo-EM Single Particle Analysis.
abstract: Genome uncoating is a prerequisite for the successful infection of plant viruses in host plants. Thus far, little is known about the genome uncoating of the Carnation mottle virus (CarMV). Here, we obtained two reconstructions of CarMV at pH7 in the presence (Ca-pH7) and absence (EDTA-pH7) of calcium ions by Cryo-EM single particle analysis, which achieved 6.4 Å and 8 Å resolutions respectively. Our results showed that chelation of the calcium ions under EDTA-pH7 resulted in reduced interaction between the subunits near the center of the asymmetric unit but not overall size change of the viral particles, which indicated that the role of the calcium ions in CarMV was not predominantly for the structural preservation. Part of the genomic RNA closest to the capsid was found to be located near the center of the asymmetric unit, which might result from the interaction between genomic RNA and Lys194 residues. Together with the electrostatic potential analysis on the inner surface of the asymmetric unit, the reduced interaction near the center of the asymmetric unit under EDTA-pH7 suggested that the genome release of CarMV might be realized through the center of the asymmetric unit.
authors.affiliation: College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Qin-Fen
authors.initials: QF
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Yuan-Zhu
authors.initials: YZ
authors.lastname: Gao
authors.affiliation: Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
authors.forename: Li
authors.initials: L
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Li
authors.affiliation: College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Hong
authors.affiliation: College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
authors.forename: Chuan-Xi
authors.initials: CX
authors.lastname: Zhang
mesh_terms: D002118:Calcium / Q000737:chemistry; D002213:Capsid / Q000737:chemistry; D019184:Carmovirus / Q000737:chemistry* / Q000235:genetics; D020285:Cryoelectron Microscopy / Q000379:methods*; D004492:Edetic Acid / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008239:Lysine / Q000737:chemistry; D012367:RNA, Viral / Q000737:chemistry; D055672:Static Electricity
chemical_list: D012367:RNA, Viral; D004492:Edetic Acid; D008239:Lysine; D002118:Calcium