Alphaviruses are enveloped RNA viruses that contain several human pathogens. Due to intrinsic heterogeneity of alphavirus particles, a high resolution structure of the virion is currently lacking. Here we provide a 3.5 Å cryo-EM structure of Sindbis virus, using block based reconstruction method that overcomes the heterogeneity problem. Our structural analysis identifies a number of conserved residues that play pivotal roles in the virus life cycle. We identify a hydrophobic pocket in the subdomain D of E2 protein that is stabilized by an unknown pocket factor near the viral membrane. Residues in the pocket are conserved in different alphaviruses. The pocket strengthens the interactions of the E1/E2 heterodimer and may facilitate virus assembly. Our study provides structural insights into alphaviruses that may inform the design of drugs and vaccines.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294011 | PMC |
http://dx.doi.org/10.1038/s41467-018-07704-x | DOI Listing |
Structure
January 2025
Department of Biochemistry, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN 37232, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA. Electronic address:
mRNAs are packaged with proteins into messenger ribonucleoprotein complexes (mRNPs) in the nucleus. mRNP assembly and export are of fundamental importance for all eukaryotic gene expression. Before export to the cytoplasm, mRNPs undergo dynamic remodeling governed by the DEAD-box helicase DDX39B (yeast Sub2).
View Article and Find Full Text PDFViruses
December 2024
Department of Microbiology and Immunology, Penn State College of Medicine, Hershey, PA 17033, USA.
Since the discovery of the Australia antigen, now known as the hepatitis B surface antigen (HBsAg), significant research has been conducted to elucidate its physical, chemical, structural, and functional properties. Subviral particles (SVPs) containing HBsAg are highly immunogenic, non-infectious entities that have not only revolutionized vaccine development but also provided critical insights into HBV immune evasion and viral assembly. Recent advances in cryo-electron microscopy (cryo-EM) have uncovered the heterogeneity and dynamic nature of spherical HBV SVPs, emphasizing the essential role of lipid-protein interactions in maintaining particle stability.
View Article and Find Full Text PDFMolecules
January 2025
Department of Chemistry, Ball State University, Muncie, IN 47306, USA.
Ipomoeassin F (Ipom-F) is a plant-derived macrocyclic resin glycoside that potently inhibits cancer cell growth through blockage of Sec61-mediated protein translocation at the endoplasmic reticulum. Recently, detailed structural information on how Ipom-F binds to Sec61α was obtained using Cryo-EM, which discovered that polar interactions between asparagine-300 (N300) in Sec61α and four oxygens in Ipom-F are crucial. One of the four oxygens is from the carbonyl group at C-4 of the fatty acid chain.
View Article and Find Full Text PDFMicroorganisms
January 2025
Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
Goose parvovirus (GPV) is an etiological agent of Derzsy's disease, afflicting geese and Muscovy ducks worldwide. Its high mortality rate among goslings and ducklings causes large losses to the waterfowl industry. Toward molecular and structural characterization, virus-like particles (VLPs) of GPV were produced, and the capsid structure was determined by cryogenic electron microscopy (cryo-EM) at a resolution of 2.
View Article and Find Full Text PDFGenes (Basel)
January 2025
Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Background: Eukaryotic RNA polymerase I consists of 12 or 11 core subunits and three dissociable subunits, Rrn3, A34, and A49. The A34 and A49 subunits exist as a heterodimer. In silico analysis of the A34 family of transcription factors demonstrates a commonly shared domain structure despite a lack of sequence conservation, as well as N-terminal and C-terminal disordered regions.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!