Skip Navigation



Nucleic Acids Research Advance Access published online on July 6, 2009
Nucleic Acids Research, doi:10.1093/nar/gkp563
This Article
Right arrow Full Text Freely available
Right arrow Print PDF (405K) Freely available
Right arrow Screen PDF (2511K) Freely available
Right arrow Supplementary Data
Right arrowOA All Versions of this Article:
37/16/5559    most recent
gkp563v1
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 Commercial Re-use Guidelines
for Open Access NAR Content
Google Scholar
Right arrow Articles by Guédin, A.
Right arrow Articles by Mergny, J.-L.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Guédin, A.
Right arrow Articles by Mergny, J.-L.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2009 The Author(s)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Structural Biology

Stability of intramolecular quadruplexes: sequence effects in the central loop

Aurore Guédin1,2, Patrizia Alberti1,2 and Jean-Louis Mergny1,2,*

1INSERM, U565, Acides nucléiques: dynamique, ciblage et fonctions biologiques, 43 rue Cuvier, CP26, Paris Cedex 05, F-75231 and 2Muséum National d’Histoire Naturelle (MNHN) USM503, CNRS, UMR7196, Département de ‘Régulations, développement et diversité moléculaire’, Laboratoire des Régulations et dynamique des génomes, 43 rue Cuvier, CP26, Paris Cedex 5, F-75231, France

*To whom correspondence should be addressed. Tel: +33 1 40 79 36 89; Fax: +33 1 40 79 37 05l; Email: mergny{at}mnhn.fr

Received April 2, 2009. Revised June 16, 2009. Accepted June 17, 2009.

Hundreds of thousands of putative quadruplex sequences have been found in the human genome. It is important to understand the rules that govern the stability of these intramolecular structures. In this report, we analysed sequence effects in a 3-base-long central loop, keeping the rest of the quadruplex unchanged. A first series of 36 different sequences were compared; they correspond to the general formula GGGTTTGGGHNHGGGTTTGGG. One clear rule emerged from the comparison of all sequence motifs: the presence of an adenine at the first position of the loop was significantly detrimental to stability. In contrast, adenines have no detrimental effect when present at the second or third position of the loop. Cytosines may either have a stabilizing or destabilizing effect depending on their position. In general, the correlation between the Tm or {Delta}G° in sodium and potassium was weak. To determine if these sequence effects could be generalized to different quadruplexes, specific loops were tested in different sequence contexts. Analysis of 26 extra sequences confirmed the general destabilizing effect of adenine as the first base of the loop(s). Finally, analysis of some of the sequences by microcalorimetry (DSC) confirmed the differences found between the sequence motifs.


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.