Quick Search:

uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive 

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-14585

Geacintov, N E; Broyde, S; Buterin, T; Naegeli, H; Wu, M; Yan, S; Patel, D J (2002). Thermodynamic and structural factors in the removal of bulky DNA adducts by the nucleotide excision repair machinery. Biopolymers, 65(3):202-210.

[img] PDF - Registered users only
1MB

Abstract

The function of the human nucleotide excision repair (NER) apparatus is to remove bulky adducts from damaged DNA. In an effort to gain insights into the molecular mechanisms involved in the recognition and excision of bulky lesions, we investigated a series of site specifically modified oligonucleotides containing single, well-defined polycyclic aromatic hydrocarbon (PAH) diol epoxide-adenine adducts. Covalent adducts derived from the bay region PAH, benzo[a]pyrene, are removed by human NER enzymes in vitro. In contrast, the stereochemically analogous N(6)-dA adducts derived from the topologically different fjord region PAH, benzo[c]phenanthrene, are resistant to repair. The evasion of DNA repair may play a role in the observed higher tumorigenicity of the fjord region PAH diol epoxides. We are elucidating the structural and thermodynamic features of these adducts that may underlie their marked distinction in biologic function, employing high-resolution nuclear magnetic resonance studies, measurements of thermal stabilities of the PAH diol epoxide-modified oligonucleotide duplexes, and molecular dynamics simulations with free energy calculations. Our combined findings suggest that differences in the thermodynamic properties and thermal stabilities are associated with differences in distortions to the DNA induced by the lesions. These structural effects correlate with the differential NER susceptibilities and stem from the intrinsically distinct shapes of the fjord and bay region PAH diol epoxide-N(6)-adenine adducts.

Item Type:Journal Article, refereed, further contribution
Communities & Collections:05 Vetsuisse Faculty > Institute of Veterinary Pharmacology and Toxicology
DDC:570 Life sciences; biology
Language:English
Date:2002
Deposited On:26 Mar 2009 08:54
Last Modified:28 Nov 2013 00:41
Publisher:Wiley-Blackwell
ISSN:0006-3525
Funders:Swiss National Science Foundation
Publisher DOI:10.1002/bip.10239
PubMed ID:12228925
Citations:Web of Science®. Times Cited: 79
Google Scholar™
Scopus®. Citation Count: 85

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page