TY - JOUR T1 - The isolation of proteins on nascent DNA (iPOND) reveals a role for RIF1 in the organization of replication factories JF - bioRxiv DO - 10.1101/669234 SP - 669234 AU - Cyril Ribeyre AU - Rana Lebdy AU - Julie Patouillard AU - Marion Larroque AU - Raghida Abou-Merhi AU - Christian Larroque AU - Angelos Constantinou Y1 - 2020/01/01 UR - http://biorxiv.org/content/early/2020/04/15/669234.abstract N2 - Eukaryotic genomes are duplicated from thousands of replication origins that fire sequentially forming a defined spatiotemporal pattern of replication clusters. The importance of the organization of replisomes into functional clusters, called replication factories, is still poorly understood. Here we show that the isolation of Proteins On Nascent DNA (iPOND) method is strongly dependent on the organization level of replication factories. We find that RIF1 is a component of replication factories. The purification of replication-associated proteins from RIF1-depleted cells using iPOND reveals a major defect in the clustering of replication factors upon mild replicative stress. The loss of organization caused by RIF1 depletion leads to defects in replication forks dynamic and yields DNA lesions. We propose a model whereby RIF1 encases replication factories to prevent the formation of DNA lesions in response to replicative stress. The data highlight the importance of the organization of replication factories for the maintenance of genome integrity.Competing Interest StatementThe authors have declared no competing interest. ER -