Skip Navigation



Journal of Biochemistry Advance Access published online on March 18, 2009
Journal of Biochemistry, doi:10.1093/jb/mvp048
This Article
Right arrow Advance Access manuscript (PDF)
Right arrow Supplementary Data
Right arrow Supplementary Data
Right arrow All Versions of this Article:
146/1/77    most recent
mvp048v1
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 Xue, Y.
Right arrow Articles by Feng, X.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Xue, Y.
Right arrow Articles by Feng, X.
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.

Influence of Magnesium Ion on the Binding of p53 DNA Binding Domain to DNA Response Elements

Yonglai Xue, Shuai Wang and Xizeng Feng*

College of Life Science, Nankai University at Tianjin, P. R. China 300071

*Address correspondence to: Xizeng Feng. Telephone: +86-22-2350-7022; Fax: +86-22-2350-7022; E-mail: xzfeng{at}nankai.edu.cn

Received January 14, 2009; Accepted March 2, 2009


  Abstract

Site-specific recognition and DNA-binding activity of p53 are crucial for its tumor suppressor function. Previous reports have shown that metal ions can affect the specific recognition and DNA-binding activity of p53DBD. Here we firstly report that magnesium ion can bind to the protein and influence its DNA-binding activity. To elucidate the nature and the effect of metal ions in the reaction chemistry, we utilized endogenous tryptophan fluorescence to quantitate the interaction between p53DBD and metal ions. The Ka value for the binding of Mg2+ to the protein is 1.88x103 M–1. Analysis of the CD data clearly suggested that the binding of magnesium ion induced a subtle conformational change rather than a radical modification of the overall protein architecture. Based on the results of electrophoretic mobility shift assays and fluorescence experiments, we concluded that the binding of Mg2+ significantly stimulated the binding of the protein to DNA in a sequence-independent manner, which differed from that of zinc ions in a sequence-specific manner. Based on these results and the fact that Mg2+ exists at relatively high concentration in the cell, we propose that Mg2+ is one of potential factors to affect or regulate the transactivation of p53.

Key Words: protein-DNA interaction, DNA-binding activity, affinity, association constant, conformational change, fluorescence


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.