In Situ Structures of the Segmented Genome and RNA Polymerase Complex Inside a dsRNA Virus

Transferrin receptor binds virus capsid with dynamic motion

“…The absence of the receptor densities in the averaged 3D reconstruction was expected due to our incubation with only ∼4 TfRs per capsid. To resolve the TfRs bound to the capsid, we proceeded by applying a SMR method to solve an asymmetric structure of 1 receptor bound to the capsid (42)(43)(44)(45).…”

Reconstitution of the RNA-dependent RNA polymerase activity of Antheraea mylitta cypovirus in vitro using separately expressed different functional domains of the enzyme

“…In contrast to these polymerases, for RdRps of the family Reoviridae there are very limited data on their innate motions. Recent cryo-EM maps of BmCPV-1 virions in quiescent and transcriptionally active states have suggested a significant conformational change in the CTD of BmCPV-1 RdRp located inside the virion core (Zhang et al, 2015). However, MD simulation cannot capture such transitions in the model of AmCPV RdRp either in the quiescent or in the active form.…”

“…The mechanism of genomic RNA synthesis has not been studied in detail for any cytoplasmic polyhedrosis viruses (CPVs). Recently, a model for dsRNA synthesis has been postulated from the cryo-EM (CryoElectron Microscopy) polymerase map of Bombyx mori CPV (BmCPV-1) (Liu & Cheng, 2015;Zhang et al, 2015). Hence, a characterization of the RNA replication/transcription process mediated by cypoviral polymerases is urgently required.…”

“…No X-ray crystal structure is available for this RdRp, but a computational approach has deciphered its structure-function relationship to some extent (Kundu et al, 2015). It was found that the overall model structure of AmCPV RdRp is relevant to the structures of transcriptionally active BmCPV-1 RdRp (PDB 3JB7) (Zhang et al, 2015), orthoreovirus l3 (PDB 1N1H) (Tao et al, 2002), rotavirus VP1 (PDB 2R7O) (Lu et al, 2008) and the model structure of bluetongue virus (BTV) VP1 (Wehrfritz et al, 2007). Refinement of the reported model of AmCPV RdRp based on the coordinates of BmCPV-1 RdRp (PDB 3JB6 3JB7) has improved the quality of the model and precisely redefined the boundaries of the N-terminal domain (NTD) (residues 1-349), the polymerase domain (PD) (residues 350-879) and the C-terminal domain (CTD) (residues 880-1116) (Fig.…”

Intercellular movement of plant RNA viruses: Targeting replication complexes to the plasmodesma for both accuracy and efficiency

“…Unlike +ssRNA viruses, the replication and transcription of double‐stranded RNA (dsRNA) viruses occur in viral particles to avoid cellular dsRNA‐based immune surveillance 140‐142 . It has been shown that plant‐infecting dsRNA viruses move as intact virions via specialized tubules that formed by one or more viral proteins in their arthropod vectors, 143‐145 whereas it is unclear whether they are also transported as intact virions in plants.…”