title: Click labeling of unnatural sugars metabolically incorporated into viral envelope glycoproteins enables visualization of single particle fusion.
abstract: Enveloped viruses infect target cells by fusing their membrane with cellular membrane through a process that is mediated by specialized viral glycoproteins. The inefficient and highly asynchronous nature of viral fusion complicates studies of virus entry on a population level. Single virus imaging in living cells has become an important tool for delineating the entry pathways and for mechanistic studies of viral fusion. We have previously demonstrated that incorporation of fluorescent labels into the viral membrane and trapping fluorescent proteins in the virus interior enables the visualization of single virus fusion in living cells. Here, we implement a new approach to non-invasively label the viral membrane glycoproteins through metabolic incorporation of unnatural sugars followed by click-reaction with organic fluorescent dyes. This approach allows for efficient labeling of diverse viral fusion glycoproteins on the surface of HIV pseudoviruses. Incorporation of a content marker into surface-labeled viral particles enables sensitive detection of single virus fusion with live cells.
authors.affiliation: Division of Pediatric Infectious Diseases, Emory University School of Medicine, USA.
authors.forename: Yoon Hyeun
authors.initials: YH
authors.lastname: Oum
authors.affiliation: Division of Pediatric Infectious Diseases, Emory University School of Medicine, USA.
authors.forename: Tanay M
authors.initials: TM
authors.lastname: Desai
authors.affiliation: Division of Pediatric Infectious Diseases, Emory University School of Medicine, USA.
authors.forename: Mariana
authors.initials: M
authors.lastname: Marin
authors.affiliation: Division of Pediatric Infectious Diseases, Emory University School of Medicine, USA; Children's Healthcare of Atlanta, Atlanta, GA, USA. Electronic address: gmeliki@emory.edu.
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Melikyan
mesh_terms: D002460:Cell Line; D057930:Click Chemistry; D005456:Fluorescent Dyes; D006801:Humans; D057054:Molecular Imaging; D013194:Staining and Labeling; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000378:metabolism*; D014760:Viral Fusion Proteins / Q000737:chemistry / Q000378:metabolism*; D014771:Virion / Q000378:metabolism*; D053586:Virus Internalization
chemical_list: D005456:Fluorescent Dyes; D014759:Viral Envelope Proteins; D014760:Viral Fusion Proteins
keywords: Click chemistry; Live cell imaging; Metabolic labeling; Retrovirus; Unnatural sugar; Vesicular stomatitis virus