BLM Associated Protein 18kDa (BLAP18)

RMI2 is a component of the BLM (RECQL3) complex, which plays a role in homologous recombination-dependent DNA repair and is essential for genome stability.The deduced 147-amino acid protein has a single oligonucleotide-binding (OB)-fold domain. RMI2 had an apparent molecular mass of 18 to 20 kD by SDS-PAGE. RMI2 orthologs were detected in vertebrates and plants, but not in lower organisms.

RMI2 also associated with RMI1 and TOP3A in a second complex. RMI1 and RMI2 interacted directly, and both were essential for stability of the BLM complex. Depletion of either RMI1 or RMI2 depleted the other protein by 80 to 90%. Chicken DT40 cells depleted of Rmi2 displayed elevated sister chromatid exchange, but other functions of the BLM complex appeared intact.