DNA topoisomerase VI, subunit B, transducer (IPR015320)

Short name: TopoVI_B_transducer

Overlapping homologous superfamilies

Domain relationships



DNA topoisomerases regulate the number of topological links between two DNA strands (i.e. change the number of superhelical turns) by catalysing transient single- or double-strand breaks, crossing the strands through one another, then resealing the breaks [PMID: 7770916]. These enzymes have several functions: to remove DNA supercoils during transcription and DNA replication; for strand breakage during recombination; for chromosome condensation; and to disentangle intertwined DNA during mitosis [PMID: 12042765, PMID: 11395412]. DNA topoisomerases are divided into two classes: type I enzymes (EC:; topoisomerases I, III and V) break single-strand DNA, and type II enzymes (EC:; topoisomerases II, IV and VI) break double-strand DNA [PMID: 12596227].

Type II topoisomerases are ATP-dependent enzymes, and can be subdivided according to their structure and reaction mechanisms: type IIA (topoisomerase II or gyrase, and topoisomerase IV) and type IIB (topoisomerase VI). These enzymes are responsible for relaxing supercoiled DNA as well as for introducing both negative and positive supercoils [PMID: 7980433].

This entry represents subunit B of topoisomerase VI, an ATP-dependent type IIB enzyme. Members of this family adopt a structure consisting of a four-stranded beta-sheet backed by three alpha-helices, the last of which is over 50 amino acids long and extends from the body of the protein by several turns. This domain has been proposed to mediate intersubunit communication by structurally transducing signals from the ATP binding and hydrolysis domains to the DNA binding and cleavage domains of the gyrase holoenzyme [PMID: 12505993].

GO terms

Biological Process

GO:0006265 DNA topological change

Molecular Function

GO:0003677 DNA binding
GO:0003918 DNA topoisomerase type II (ATP-hydrolyzing) activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.