title: Identification of essential filovirion-associated host factors by serial proteomic analysis and RNAi screen.
abstract: An assessment of the total protein composition of filovirus (ebolavirus and marburgvirus) virions is currently lacking. In this study, liquid chromatography-linked tandem mass spectrometry of purified ebola and marburg virions was performed to identify associated cellular proteins. Host proteins involved in cell adhesion, cytoskeleton, cell signaling, intracellular trafficking, membrane organization, and chaperones were identified. Significant overlap exists between this data set and proteomic studies of disparate viruses, including HIV-1 and influenza A, generated in multiple cell types. However, the great majority of proteins identified here have not been previously described to be incorporated within filovirus particles. Host proteins identified by liquid chromatography-linked tandem mass spectrometry could lack biological relevance because they represent protein contaminants in the virus preparation, or because they are incorporated within virions by chance. These issues were addressed using siRNA library-mediated gene knockdown (targeting each identified virion-associated host protein), followed by filovirus infection. Knockdown of several host proteins (e.g. HSPA5 and RPL18) significantly interfered with ebolavirus and marburgvirus infection, suggesting specific and relevant virion incorporation. Notably, select siRNAs inhibited ebolavirus, but enhanced marburgvirus infection, suggesting important differences between the two viruses. The proteomic analysis presented here contributes to a greater understanding of filovirus biology and potentially identifies host factors that can be targeted for antiviral drug development.
authors: The United States Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA.
authors: Kevin B
authors: KB
authors: Spurgers
authors: Tim
authors: T
authors: Alefantis
authors: Brian D
authors: BD
authors: Peyser
authors: Gordon T
authors: GT
authors: Ruthel
authors: Alison A
authors: AA
authors: Bergeron
authors: Julie A
authors: JA
authors: Costantino
authors: Sven
authors: S
authors: Enterlein
authors: Krishna P
authors: KP
authors: Kota
authors: R C Dutch
authors: RC
authors: Boltz
authors: M Javad
authors: MJ
authors: Aman
authors: Vito G
authors: VG
authors: Delvecchio
authors: Sina
authors: S
authors: Bavari
mesh_terms: D000595:Amino Acid Sequence; D002853:Chromatography, Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D016563:Filoviridae / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D040901:Proteomics; D034622:RNA Interference; D053719:Tandem Mass Spectrometry; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000378:metabolism*
chemical_list: D014764:Viral Proteins