Structure of Ljungan virus provides insight into genome packaging of this picornavirus
نویسندگان
چکیده
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.
منابع مشابه
Deep Sequencing of Foot-and-Mouth Disease Virus Reveals RNA Sequences Involved in Genome Packaging
Non-enveloped viruses protect their genomes by packaging them into an outer shell or capsid of virus-encoded proteins. Packaging and capsid assembly in RNA viruses can involve interactions between capsid proteins and secondary structures in the viral genome as exemplified by the RNA bacteriophage MS2 and as proposed for other RNA viruses of plants, animals and human. In the picornavirus family ...
متن کاملMolecular analysis of three Ljungan virus isolates reveals a new, close-to-root lineage of the Picornaviridae with a cluster of two unrelated 2A proteins.
Ljungan virus (LV) is a suspected human pathogen recently isolated from bank voles (Clethrionomys glareolus). In the present study, it is revealed through comparative sequence analysis that three newly determined Swedish LV genomes are closely related and possess a deviant picornavirus-like organization: 5' untranslated region-VP0-VP3-VP1-2A1-2A2-2B-2C-3A-3B-3C-3D-3' untranslated region. The LV...
متن کاملA highly divergent picornavirus in a marine mammal.
Nucleic acids from an unidentified virus from ringed seals (Phoca hispida) were amplified using sequence-independent PCR, subcloned, and then sequenced. The full genome of a novel RNA virus was derived, identifying the first sequence-confirmed picornavirus in a marine mammal. The phylogenetic position of the tentatively named seal picornavirus 1 (SePV-1) as an outlier to the grouping of parecho...
متن کاملLimits of Structural Plasticity in a Picornavirus Capsid Revealed by a Massively Expanded Equine Rhinitis A Virus Particle
UNLABELLED The Picornaviridae family of small, nonenveloped viruses includes major pathogens of humans and animals. They have positive-sense, single-stranded RNA genomes, and the mechanism(s) by which these genomes are introduced into cells to initiate infection remains poorly understood. The structures of presumed uncoating intermediate particles of several picornaviruses show limited expansio...
متن کاملMolecular characterization of a novel Ljungan virus (Parechovirus; Picornaviridae) reveals a fourth genotype and indicates ancestral recombination.
Ljungan virus (LV) was discovered 20 years ago in Swedish bank voles (Myodes glareolus, previously referred to as Clethrionomys glareolus) during the search for an infectious agent causing lethal myocarditis in young athletes. To date, the genomes of four LV isolates, including the prototype 87-012 strain, have been characterized. Three of these LV strains were isolated from bank voles trapped ...
متن کامل