title: RNA aptamer binding to polyhistidine-tag.
abstract: Polyhistidine-tag (His-tag) is a powerful tool for purification of recombinant protein. His-tagged protein can be affinity-purified by using resins immobilizing Ni2+ or anti-His-tag antibodies. However, Ni2+-affinity-purification is prevented by the presence of divalent cations. The purification with antibodies has contamination of antibody peptides, which interferes with following analysis. In the present study, we isolated RNA aptamers binding to His-tag. The best clone, named shot47, bound to the target with low picomolar dissociation constant. In the presence of divalent cations, shot47 was substitutable for antibodies against His-tag on ELISA, immunoprecipitation, and Western blotting. Shot47 can be synthesized easily by in vitro transcription. Thus, shot47 would be applicable as a useful and cost-effective tool for biochemical analyses.
authors.affiliation: Division of Cancer Therapy, Kanagawa Cancer Center Research Institute, Yokohama-shi, Kanagawa 241-0815, Japan. stsuji@gancen.asahi.yokohama.jp
authors.forename: Shoutaro
authors.initials: S
authors.lastname: Tsuji
authors.forename: Taku
authors.initials: T
authors.lastname: Tanaka
authors.forename: Naomi
authors.initials: N
authors.lastname: Hirabayashi
authors.forename: Shintaro
authors.initials: S
authors.lastname: Kato
authors.forename: Joe
authors.initials: J
authors.lastname: Akitomi
authors.forename: Hazuki
authors.initials: H
authors.lastname: Egashira
authors.forename: Iwao
authors.initials: I
authors.lastname: Waga
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohtsu
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000302:isolation & purification; D001483:Base Sequence; D002846:Chromatography, Affinity; D006639:Histidine / Q000737:chemistry*; D008263:Macrophage Migration-Inhibitory Factors / Q000302:isolation & purification; D009690:Nucleic Acid Conformation; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification*; D012313:RNA / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D000906:Antibodies; D052157:Aptamers, Nucleotide; D008263:Macrophage Migration-Inhibitory Factors; D011506:Proteins; C033223:polyhistidine; D006639:Histidine; D012313:RNA