title: Structure of Ljungan virus provides insight into genome packaging of this picornavirus.
abstract: Picornaviruses are responsible for a range of human and animal diseases, but how their RNA genome is packaged remains poorly understood. A particularly poorly studied group within this family are those that lack the internal coat protein, VP4. Here we report the atomic structure of one such virus, Ljungan virus, the type member of the genus Parechovirus B, which has been linked to diabetes and myocarditis in humans. The 3.78-Å resolution cryo-electron microscopy structure shows remarkable features, including an extended VP1 C terminus, forming a major protuberance on the outer surface of the virus, and a basic motif at the N terminus of VP3, binding to which orders some 12% of the viral genome. This apparently charge-driven RNA attachment suggests that this branch of the picornaviruses uses a different mechanism of genome encapsidation, perhaps explored early in the evolution of picornaviruses.
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.|The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhu
authors.affiliation: National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China.
authors.forename: Xiangxi
authors.initials: X
authors.lastname: Wang
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.
authors.forename: Jingshan
authors.initials: J
authors.lastname: Ren
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.|The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Claudine
authors.initials: C
authors.lastname: Porta
authors.affiliation: The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Hannah
authors.initials: H
authors.lastname: Wenham
authors.affiliation: Department of Chemistry and Biomedical Sciences, Linnaeus University, SE-391 82 Kalmar, Sweden.
authors.forename: Jens-Ola
authors.initials: JO
authors.lastname: Ekström
authors.affiliation: The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Anusha
authors.initials: A
authors.lastname: Panjwani
authors.affiliation: The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Knowles
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.
authors.forename: Abhay
authors.initials: A
authors.lastname: Kotecha
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.
authors.forename: C Alistair
authors.initials: CA
authors.lastname: Siebert
authors.affiliation: Department of Chemistry and Biomedical Sciences, Linnaeus University, SE-391 82 Kalmar, Sweden.
authors.forename: A Michael
authors.identifier: http://orcid.org/0000-0003-3841-4826
authors.initials: AM
authors.lastname: Lindberg
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Fry
authors.affiliation: National Laboratory of Macromolecules, Institute of Biophysics, Chinese Academy of Science, Beijing 100101, China.|Laboratory of Structural Biology, School of Medicine, Tsinghua University, Beijing 100084, China.
authors.forename: Zihe
authors.initials: Z
authors.lastname: Rao
authors.affiliation: The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK.
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Tuthill
authors.affiliation: Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK.|Diamond Light Sources, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK.
authors.forename: David I
authors.initials: DI
authors.lastname: Stuart
mesh_terms: D000818:Animals; D002460:Cell Line; D020285:Cryoelectron Microscopy; D018076:DNA, Complementary; D009690:Nucleic Acid Conformation; D030061:Parechovirus / Q000502:physiology*; D012367:RNA, Viral / Q000737:chemistry / Q000502:physiology*
chemical_list: D018076:DNA, Complementary; D012367:RNA, Viral