8acb
From Proteopedia
CryoEM structure of sweet potato feathery mottle virus VLP
Structural highlights
FunctionA0A0Y0I2B8_9POTV An RNA-dependent RNA polymerase that plays an essential role in the virus replication.[ARBA:ARBA00029404] Has RNA-binding and proteolytic activities.[ARBA:ARBA00029399] Has helicase activity. It may be involved in replication.[ARBA:ARBA00029422] Indispensable for virus replication.[ARBA:ARBA00034080] Involved in aphid transmission, cell-to-cell and systemis movement, encapsidation of the viral RNA and in the regulation of viral RNA amplification.[ARBA:ARBA00029405] Mediates the cap-independent, EIF4E-dependent translation of viral genomic RNAs (By similarity). Binds to the cap-binding site of host EIF4E and thus interferes with the host EIF4E-dependent mRNA export and translation (By similarity). VPg-RNA directly binds EIF4E and is a template for transcription (By similarity). Also forms trimeric complexes with EIF4E-EIF4G, which are templates for translation.[ARBA:ARBA00037225] Required for aphid transmission and also has proteolytic activity. Only cleaves a Gly-Gly dipeptide at its own C-terminus. Interacts with virions and aphid stylets. Acts as a suppressor of RNA-mediated gene silencing, also known as post-transcriptional gene silencing (PTGS), a mechanism of plant viral defense that limits the accumulation of viral RNAs. May have RNA-binding activity.[ARBA:ARBA00029420] Publication Abstract from PubMedSweet potato feathery mottle virus (SPFMV) and Sweet potato mild mottle virus (SPMMV) are members of the genera Potyvirus and Ipomovirus, family Potyviridae, sharing Ipomoea batatas as common host, but transmitted, respectively, by aphids and whiteflies. Virions of family members consist of flexuous rods with multiple copies of a single coat protein (CP) surrounding the RNA genome. Here we report the generation of virus-like particles (VLPs) by transient expression of the CPs of SPFMV and SPMMV in the presence of a replicating RNA in Nicotiana benthamiana. Analysis of the purified VLPs by cryo-electron microscopy, gave structures with resolutions of 2.6 and 3.0 A, respectively, showing a similar left-handed helical arrangement of 8.8 CP subunits per turn with the C-terminus at the inner surface and a binding pocket for the encapsidated ssRNA. Despite their similar architecture, thermal stability studies reveal that SPMMV VLPs are more stable than those of SPFMV. CryoEM and stability analysis of virus-like particles of potyvirus and ipomovirus infecting a common host.,Chase O, Javed A, Byrne MJ, Thuenemann EC, Lomonossoff GP, Ranson NA, Lopez-Moya JJ Commun Biol. 2023 Apr 19;6(1):433. doi: 10.1038/s42003-023-04799-x. PMID:37076658[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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