title: Phosphorothioate oligonucleotides bind in a non sequence-specific manner to the nucleolar protein C23/nucleolin.
abstract: To design optimal strategies for intracellular delivery of antisense phosphorothioate oligonucleotides, it may be useful to understand their interaction with cellular macromolecules. Nuclear extracts from LOX amelanotic myeloma cells were studied for protein binding to phosphorothioate oligonucleotides using a Southwestern protocol. Multiple nuclear proteins bound to the phosphorothioate oligonucleotides but no detectable protein binding was found to phosphodiester oligonucleotides. The protein with the strongest binding signals was shown by immunoprecipitation to be nucleolar C23/nucleolin, a 110 kDa protein. With glutathione S-transferase/nucleolin fusion protein constructs, the region of nucleolin containing the RNA recognition motifs had binding activity to phosphorothioate oligonucleotides.
authors.affiliation: Department of Pharmacology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Weidner
authors.forename: B C
authors.initials: BC
authors.lastname: Valdez
authors.forename: D
authors.initials: D
authors.lastname: Henning
authors.forename: S
authors.initials: S
authors.lastname: Greenberg
authors.forename: H
authors.initials: H
authors.lastname: Busch
mesh_terms: D001483:Base Sequence; D005982:Glutathione Transferase / Q000235:genetics; D006801:Humans; D008545:Melanoma / Q000473:pathology; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D016376:Oligonucleotides, Antisense / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D011485:Protein Binding; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013873:Thionucleotides / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D000097796:Nucleolin
chemical_list: D005982:Glutathione Transferase; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense; D010750:Phosphoproteins; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D013873:Thionucleotides; D000097796:Nucleolin