CAG/CTG repeats alter the affinity for the histone core and the positioning of DNA in the nucleosome.

ABSTRACT: Trinucleotide repeats (TNRs) occur throughout the genome, and their expansion has been linked to several neurodegenerative disorders, including Huntington's disease. TNRs have been studied using both oligonucleotides and plasmids; however, less is know about how repetitive DNA responds to genomic packaging. Here, we investigate the behavior of CAG/CTG repeats incorporated into nucleosome core particles, the most basic unit of chromatin packaging. To assess the general interaction between CAG/CTG repeats and the histone core, we determined the efficiency with which various TNR-containing DNA substrates form nucleosomes, revealing that even short CAG/CTG tracts are robust incorporators. However, the presence of the Huntington gene flanking sequence (htt) decreases the rate of incorporation.

SUBMITTER: Volle CB 

PROVIDER: S-EPMC3567209 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature