A nucleotide resolution map of Top2-linked DNA breaks in the yeast and human genome
William Gittens, Dominic J. Johnson, Rachal M. Allison, Tim J. Cooper, Holly Thomas, and Matthew J Neale
Received Date: 7th February 19
DNA topoisomerases are required to resolve DNA topological stress. Despite this essential role, abortive topoisomerase activity generates aberrant protein-linked DNA breaks, jeopardising genome stability. Here, to understand the genomic distribution and mechanisms underpinning topoisomerase-induced DNA breaks, we map Top2 DNA cleavage with strand-specific nucleotide resolution across the S. cerevisiaeand human genomes—and use the meiotic Spo11 protein to validate the broad applicability of this method to explore the role of diverse topoisomerase family members. Our data characterises Mre11-dependent repair in yeast, and defines two strikingly different fractions of Top2 activity in humans: tightly localised CTCF-proximal, and broadly distributed transcription-proximal, the latter correlated with gene length and expression. Moreover, single nucleotide accuracy enables us to reveal the influence primary DNA sequence has upon Top2 cleavage—distinguishing canonical DNA double-strand breaks (DSBs) from a major population of DNA single-strand breaks (SSBs) induced by etoposide (VP16) in vivo.
Read in full at bioRxiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.