title: Screening of functional antidotes of RNA aptamers against bovine thrombin.
abstract: A specific RNA aptamer (T705) against bovine thrombin had been obtained after seven rounds of SELEX (systematic evolution of ligands by exponential enrichment) selection from a random RNA library previously. In order to further investigate the relationship between the structure and function of this aptamer, three truncated RNA aptamers, T705a, T705b and T705c, were designed according to the secondary structure of T705 RNA. Our results showed that T705c keeping the precise stem-loop structure but lacking most of the stem region sequence of T705 could inhibit clot formation in vitro in the same way as its parental form. We also report here that single-stranded DNA (ssDNA) antisense oligonucleotides, c' and c'-22, which were complementary to different portions of T705c could act as efficient antidotes reversing the inhibitory activity of T705. It is demonstrated for the first time that ssDNA antisense oligonucleotides are potential antidotes of RNA aptamers and this may be an effective, rapid strategy to find antidotes of RNA aptamers which would be of important usefulness in basic research and drug screening.
authors.affiliation: Beijing Institute of Basic Medical Sciences, P.O. Box 130 (3), Beijing 100850, PR China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Liu
authors.forename: Guojun
authors.initials: G
authors.lastname: Cao
authors.forename: Hongmei
authors.initials: H
authors.lastname: Ding
authors.forename: Dajin
authors.initials: D
authors.lastname: Zhang
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.forename: Nongle
authors.initials: N
authors.lastname: Liu
authors.forename: Ming
authors.initials: M
authors.lastname: Fan
authors.forename: Beifen
authors.initials: B
authors.lastname: Shen
authors.forename: Ningsheng
authors.initials: N
authors.lastname: Shao
mesh_terms: D000818:Animals; D002417:Cattle; D004277:DNA, Single-Stranded / Q000235:genetics / Q000378:metabolism; D006801:Humans; D009690:Nucleic Acid Conformation; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000378:metabolism; D012313:RNA / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013917:Thrombin / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D004277:DNA, Single-Stranded; D016376:Oligonucleotides, Antisense; D012313:RNA; D013917:Thrombin