Age-Dependent Ribosomal DNA Variations in Mice.

ABSTRACT: The rRNA gene, which consists of tandem repetitive arrays (ribosomal DNA [rDNA] repeat), is one of the most unstable regions in the genome. The rDNA repeat in the budding yeast Saccharomyces cerevisiae is known to become unstable as the cell ages. However, it is unclear how the rDNA repeat changes in aging mammalian cells. Using quantitative single-cell analyses, we identified age-dependent alterations in rDNA copy number and levels of methylation in mice. The degree of methylation and copy number of rDNA from bone marrow cells of 2-year-old mice were increased by comparison to levels in 4-week-old mice in two mouse strains, BALB/cA and C57BL/6. Moreover, the level of pre-rRNA transcripts was reduced in older BALB/cA mice. We also identified many sequence variations in the rDNA. Among them

SUBMITTER: Watada E 

PROVIDER: S-EPMC7588874 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature