Extrachromosomal circular DNA of tandemly repeated genomic sequences in Drosophila.

ABSTRACT: One characteristic of genomic plasticity is the presence of extrachromosomal circular DNA (eccDNA). This DNA is found in various eukaryotes from yeast to humans, and its levels are elevated by exposure to carcinogens. eccDNA is heterogeneous in size and composed of chromosomal sequences. In this study we used two-dimensional gel electrophoresis to detect and characterize eccDNA in Drosophila. We found eccDNA throughout the fly's life cycle. These molecules comprise up to 10% of the total repetitive DNA content, and their size ranges from <1 kb to >20 kb. The eccDNA population contains circular multimers of tandemly repeated genes such as histones, rDNA, Stellate, and the Suppressor of Stellate. Multimers of centromeric heterochromatin sequences are included in eccDNA as well. Our findings

SUBMITTER: Cohen S 

PROVIDER: S-EPMC403641 | biostudies-literature | 2003 Jun

REPOSITORIES: biostudies-literature