6ehm
Model of the Ebola virus nucleocapsid subunit from recombinant virus-like particlesModel of the Ebola virus nucleocapsid subunit from recombinant virus-like particles
Structural highlights
Function[NCAP_EBOZM] Encapsidates the genome, protecting it from nucleases. The encapsidated genomic RNA is termed the nucleocapsid and serves as template for transcription and replication. During replication, encapsidation by NP is coupled to RNA synthesis and all replicative products are resistant to nucleases. [VP24_EBOZM] Prevents the establishment of cellular antiviral state by blocking the interferon-alpha/beta (IFN-alpha/beta) and IFN-gamma signaling pathways. Blocks the IFN-induced nuclear accumulation of host phosphorylated STAT1, by interacting with the STAT1-binding region of host importin alpha-1/KPNA1 protein, thereby inhibiting the latter. Without the activity of this protein, activated STAT1 would not enter the nucleus and be unable to activate IFN-induced genes. Plays a role in assembly of viral nucleocapsid and virion budding. May act as a minor matrix protein that plays a role in assembly of viral nucleocapsid and virion budding.[1] [2] [3] [4] Publication Abstract from PubMedEbola and Marburg viruses are filoviruses: filamentous, enveloped viruses that cause haemorrhagic fever. Filoviruses are within the order Mononegavirales, which also includes rabies virus, measles virus, and respiratory syncytial virus. Mononegaviruses have non-segmented, single-stranded negative-sense RNA genomes that are encapsidated by nucleoprotein and other viral proteins to form a helical nucleocapsid. The nucleocapsid acts as a scaffold for virus assembly and as a template for genome transcription and replication. Insights into nucleoprotein-nucleoprotein interactions have been derived from structural studies of oligomerized, RNA-encapsidating nucleoprotein, and cryo-electron microscopy of nucleocapsid or nucleocapsid-like structures. There have been no high-resolution reconstructions of complete mononegavirus nucleocapsids. Here we apply cryo-electron tomography and subtomogram averaging to determine the structure of Ebola virus nucleocapsid within intact viruses and recombinant nucleocapsid-like assemblies. These structures reveal the identity and arrangement of the nucleocapsid components, and suggest that the formation of an extended alpha-helix from the disordered carboxy-terminal region of nucleoprotein-core links nucleoprotein oligomerization, nucleocapsid condensation, RNA encapsidation, and accessory protein recruitment. Structure and assembly of the Ebola virus nucleocapsid.,Wan W, Kolesnikova L, Clarke M, Koehler A, Noda T, Becker S, Briggs JAG Nature. 2017 Nov 16;551(7680):394-397. doi: 10.1038/nature24490. Epub 2017 Nov 8. PMID:29144446[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|