RMI1 (RecQ-mediated genome instability protein 1) forms a conserved BTR complex with BLM, Topo and RMI2, and its absence causes genome instability. It has been revealed that RMI1 localizes to nuclear foci with BLM and Topo Ilia in response to replication stress, and that RMI1 functions downstream of BLM in promoting replication elongation. However, the precise functions of RMI1 during replication stress are not completely understood. Here we report that RMII knockdown cells are hypersensitive to hydroxyurea (HU). Using comet assay, we show that RMI1 knockdown cells exhibit accumulation of broken DNAs after being released from HU treatment. Moreover, we demonstrate that RMII facilitates the recovery from activated checkpoint and resuming the cell cycle after replicative stress. Surprisingly, loss of RMI1 results in a failure of RAD51 loading onto DNA damage sites. These findings reveal the importance of RMII in response to replication stress, which could explain the molecular basis for its function in maintaining genome integrity. (C) 2017 The Authors. Published by Elsevier Inc.