title: Enhanced in vivo imaging of metabolically biotinylated cell surface reporters.
abstract: Metabolic biotinylation of intracellular and secreted proteins as well as surface receptors in mammalian cells provides a versatile way to monitor gene expression; to purify and target viral vectors; to monitor cell and tumor distribution in real time in vivo; to label cells for isolation; and to tag proteins for purification, localization, and trafficking. Here, we show that metabolic biotinylation of proteins fused to the bacterial biotin acceptor peptides (BAP) varies among different mammalian cell types and can be enhanced by over 10-fold upon overexpression of the bacterial biotin ligase directed to the same cellular compartment as the fusion protein. We also show that in vivo imaging of metabolically biotinylated cell surface receptors using streptavidin conjugates is significantly enhanced upon coexpression of bacterial biotin ligase in the secretory pathway. These findings have practical applications in designing more efficient targeting and imaging strategies.
authors.affiliation: Neuroscience Center, Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Niers
authors.forename: John W
authors.initials: JW
authors.lastname: Chen
authors.forename: Ralph
authors.initials: R
authors.lastname: Weissleder
authors.forename: Bakhos A
authors.initials: BA
authors.lastname: Tannous
mesh_terms: D000818:Animals; D001710:Biotin / Q000737:chemistry*; D019731:Carbon-Nitrogen Ligases / Q000378:metabolism; D002460:Cell Line; D006801:Humans; D008565:Membrane Proteins / Q000032:analysis* / Q000378:metabolism*; D051379:Mice
chemical_list: D008565:Membrane Proteins; D001710:Biotin; D019731:Carbon-Nitrogen Ligases