Editor's Summary
31 March 2005
DNA damage limitation
Oxidative DNA damage is thought to be involved in tumorigenesis, and specifically the enzyme 'hOGG1' that identifies 8-oxoguanine (differing in just two atoms from normal guanine) has been linked to lung and possibly kidney cancer. A structural study in which hOGG1 (8-oxoguanine DNA glycosylase I) was trapped in the act of testing normal DNA for defects shows how it performs the essential gate-keeping role. Surprisingly, the guanine residue is not inserted into the lesion-recognition pocket, but is located at an alternative extrahelical site. This helps explain how DNA repair proteins can locate lesions embedded in a vast excess of normal DNA and can remove nucleosides from the DNA helix without damaging normal bases.
News and Views: Structural biology: DNA search and rescue
How do DNA-repair enzymes find aberrant nucleotides among the myriad of normal ones? One enzyme has been caught in the act of checking for damage, providing clues to its quality-control process.
Sheila S. David
doi:10.1038/434569a
Article: Structure of a repair enzyme interrogating undamaged DNA elucidates recognition of damaged DNA
Anirban Banerjee, Wei Yang, Martin Karplus and Gregory L. Verdine
doi:10.1038/nature03458
Abstract | Full Text | PDF (452K) | Supplementary information