Tags: Protein.
DNA topoisomerase 1 is an enzyme that in humans is encoded by the TOP1 gene.This gene encodes a DNA topoisomerase an enzyme that controls and alters the topologic states of DNA during transcription. This enzyme catalyzes the transient breaking and rejoining of a single strand of DNA which allows the strands to pass through one another thus altering the topology of DNA. This gene is localized to chromosome 20 and has pseudogenes which reside on chromosomes 1 and 22.