title: Boronic Acid for the Traceless Delivery of Proteins into Cells.
abstract: The use of exogenous proteins as intracellular probes and therapeutic agents is in its infancy. A major hurdle has been the delivery of native proteins to an intracellular site of action. Herein, we report on a compact delivery vehicle that employs the intrinsic affinity of boronic acids for the carbohydrates that coat the surface of mammalian cells. In the vehicle, benzoxaborole is linked to protein amino groups via a "trimethyl lock." Immolation of this linker is triggered by cellular esterases, releasing native protein. Efficacy is demonstrated by enhanced delivery of green fluorescent protein and a cytotoxic ribonuclease into mammalian cells. This versatile strategy provides new opportunities in chemical biology and pharmacology.
authors.affiliation: Graduate Program in Molecular and Cellular Pharmacology, University of Wisconsin-Madison , 1300 University Avenue, Madison, Wisconsin 53706, United States.
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Andersen
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Smith
authors.affiliation: Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison , 1525 Linden Drive, Madison, Wisconsin 53706, United States.
authors.forename: Jo E
authors.initials: JE
authors.lastname: Lomax
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.|Department of Biochemistry, University of Wisconsin-Madison , 433 Babcock Drive, Madison, Wisconsin 53706, United States.
authors.forename: Ronald T
authors.initials: RT
authors.lastname: Raines
mesh_terms: D000818:Animals; D001897:Boronic Acids / Q000737:chemistry* / Q000378:metabolism; D016466:CHO Cells; D045744:Cell Line, Tumor; D002463:Cell Membrane Permeability; D003412:Cricetulus; D004337:Drug Carriers / Q000737:chemistry* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D006801:Humans; D008958:Models, Molecular; D012260:Ribonucleases / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D001897:Boronic Acids; D004337:Drug Carriers; D049452:Green Fluorescent Proteins; D012260:Ribonucleases