Skip Navigation


Journal of Biochemistry Advance Access originally published online on April 7, 2009
Journal of Biochemistry 2009 146(2):173-183; doi:10.1093/jb/mvp059
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
146/2/173    most recent
mvp059v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Torigoe, H.
Right arrow Articles by Katayama, T.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Torigoe, H.
Right arrow Articles by Katayama, T.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Authors 2009. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved

Thermodynamic and Kinetic Effects of Morpholino Modification on Pyrimidine Motif Triplex Nucleic Acid Formation under Physiological Condition

Hidetaka Torigoe*, Kiyomi Sasaki and Takuma Katayama

Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan

*To whom correspondence should be addressed. Tel: +81-3-5228-8259, Fax: +81-3-5261-4631, E-mail: htorigoe{at}rs.kagu.tus.ac.jp

Received December 13, 2008; Accepted March 23, 2009


  Abstract

Due to instability of pyrimidine motif triplex nucleic acid under physiological pH and low magnesium ion concentration, stabilization of the triplex under the physiological condition is crucial in improving its therapeutic potential to artificially control gene expression in vivo. To this end, we investigated the thermodynamic and kinetic effects of morpholino (MOR) modification of triplex-forming oligonucleotide (TFO) on the triplex formation under the physiological condition. The thermodynamic analyses indicated that the MOR modification of TFO not only significantly increased the thermal stability of the triplex but also increased the binding constant for the triplex formation by nearly 2 orders of magnitude. The consideration of the observed thermodynamic parameters suggested that the increased rigidity of the MOR-modified TFO in the free state relative to the corresponding unmodified TFO may enable the significant increase in the binding constant. Kinetic data demonstrated that the observed increase in the binding constant resulted from the considerable increase in the association rate constant rather than the decrease in the dissociation rate constant. This information will be valuable for designing novel chemically modified TFO with higher binding affinity in the triplex formation under physiological conditions, leading to progress in therapeutic applications of the antigene strategy in vivo.

Key Words: triplex nucleic acid, triplex-forming oligonucleotide, morpholino modification, isothermal titration calorimetry, interaction analysis system

Abbreviations: TFO, triplex-forming oligonucleotide; MOR, morpholino; PO, natural phosphodiester; Bt, biotinylated; EMSA, electrophoretic mobility shift assay; Tm, melting temperature; CD, circular dichroism; ITC, isothermal titration calorimetry; IAsys, interaction analysis system; kon, on-rate constant; kassoc, association rate constant; koff, off-rate constant; kdissoc, dissociation rate constant


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.