Essential component of the RMI complex, a complex that plays an important role in the processing of homologous recombination intermediates. It is required to regulate sister chromatid segregation and to limit DNA crossover. Essential for the stability, localization, and function of BLM, TOP3A, and complexes containing BLM. In the RMI complex, it is required to target BLM to chromatin and stress-induced nuclear foci and mitotic phosphorylation of BLM. Component of the RMI complex, containing at least TOP3A, RMI1 and RMI2. The RMI complex interacts with BLM (By similarity). Colocalizes with BLM at nuclear DNA repair foci. Phosphorylated during mitosis. Belongs to the RMI2 family.