FORK-seq: replication landscape of the Saccharomyces cerevisiae genome by nanopore sequencing
Magali Hennion, Jean‐Michel Arbona, Laurent Lacroix, Corinne Cruaud, Bertrand Theulot, Benoît Le Tallec, Florence Proux, Xia Wu, Elizaveta Novikova, Stéfan Engelen, Arnaud Lemainque, Benjamin Audit, Olivier Hyrien
Abstract
Genome replication mapping methods profile cell populations, masking cell-to-cell heterogeneity. Here, we describe FORK-seq, a nanopore sequencing method to map replication of single DNA molecules at 200-nucleotide resolution. By quantifying BrdU incorporation along pulse-chased replication intermediates from Saccharomyces cerevisiae, we orient 58,651 replication tracks reproducing population-based replication directionality profiles and map 4964 and 4485 individual initiation and termination events, respectively. Although most events cluster at known origins and fork merging zones, 9% and 18% of initiation and termination events, respectively, occur at many locations previously missed. Thus, FORK-seq reveals the full extent of cell-to-cell heterogeneity in DNA replication.