The structural location of DNA lesions in nucleosome core particles determines accessibility by base excision repair enzymes.

ABSTRACT:

Background

Base excision repair is hindered by nucleosomes.

Results

Outwardly oriented uracils near the nucleosome center are efficiently cleaved; however, polymerase β is strongly inhibited at these sites.

Conclusion

The histone octamer presents different levels of constraints on BER, dependent on the structural requirements for enzyme activity.

Significance

Chromatin remodeling is necessary to prevent accumulation of aborted intermediates in nucleosomes. Packaging of DNA into chromatin affects accessibility of DNA regulatory factors involved in transcription, replication, and repair. Evidence suggests that even in the nucleosome core particle (NCP), accessibility to damaged DNA is hindered by the presence of the histone octamer. Base excision repair is the ma

SUBMITTER: Rodriguez Y 

PROVIDER: S-EPMC3650422 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature