DNA topoisomerase 3-beta-1(TOP3B), an enzyme that controls and alters the topologic states of DNA during transcription. TOP3B catalyzes the transient breaking and rejoining of a single strand of DNA which allows the strands to pass through one another, thus relaxing the supercoils and altering the topology of DNA. TOP3B interacts with DNA helicase SGS1 and plays a role in DNA recombination, cellular aging and maintenance of genome stability. Low expression of TOP3B may be related to higher survival rates in breast cancer patients.
