Gene silencing induced by oxidative DNA base damage: association with local decrease of histone H4 acetylation in the promoter region.

ABSTRACT: Oxidized DNA bases, particularly 7,8-dihydro-8-oxoguanine (8-oxoG), are endogenously generated in cells, being a cause of carcinogenic mutations and possibly interfering with gene expression. We found that expression of an oxidatively damaged plasmid DNA is impaired after delivery into human host cells not only due to decreased retention in the transfected cells, but also due to selective silencing of the damaged reporter gene. To test whether the gene silencing was associated with a specific change of the chromatin structure, we determined the levels of histone modifications related to transcriptional activation (acetylated histones H3 and H4) or repression (methylated K9 and K27 of the histone H3, and histone H1) in the promoter region and in the downstream transcribed DNA. Acetylation o

SUBMITTER: Khobta A 

PROVIDER: S-EPMC2910050 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature