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Protein Domain : IPR004085

Name  DNA topoisomerase VI, subunit A Short Name  TopoVI_A
Type  Family Description  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 []. 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 [, ]. DNA topoisomerases are divided into two classes: type I enzymes (; topoisomerases I, III and V) break single-strand DNA, and type II enzymes (; topoisomerases II, IV and VI) break double-strand DNA [].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 [].This entry represents subunit A of topoisomerase VI, a type IIB topoisomerase found predominantly in archaea, but also in a few eukayotes, such as the plant Arabidopsis thaliana[]. This enzyme assembles as a heterotetramer, consisting of two A subunits required for DNA cleavage and two B subunits required for ATP hydrolysis. The B subunit is structurally similar to the ATPase domain of type IIA topoisomerases, but the A subunit is distinct, and instead shares homology with the Spo11 protein that mediates double-strand DNA breaks during meiotic recombination in eukaryotes []. The core of subunit A is a dimer, with a deep groove in which the DNA molecule is thought to bind, with the monomers separating during DNA transport. Therefore, though related to type IIA topoisomerases, topoisomerase VI may have a distinctive mechanism of action.

Publication Counts Displayer

0 Child Features

2 Contains

DB identifier Name Short Name Type
IPR011991 Winged helix-turn-helix DNA-binding domain WHTH_DNA-bd_dom Domain
IPR013049 Spo11/DNA topoisomerase VI, subunit A, N-terminal Spo11/TopoVI_A_N Domain

2 Cross References

Identifier
Source . Name

Subject . Primary Identifier
PR01552 PRINTS IPR004085
MF_00132 HAMAP IPR004085

3 Data Sets

Name URL
TrEMBL data set http://www.ebi.ac.uk/trembl/
InterPro data set  
InterPro GO Annotation data set  

0 Found In

4 GO Annotation


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
DNA topoisomerase VI, subunit A   GO:0003677 DNA binding
DNA topoisomerase VI, subunit A   GO:0003918 DNA topoisomerase type II (ATP-hydrolyzing) activity
DNA topoisomerase VI, subunit A   GO:0006265 DNA topological change
DNA topoisomerase VI, subunit A   GO:0005694 chromosome

4 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
DNA topoisomerase VI, subunit A   GO:0003677 DNA binding
DNA topoisomerase VI, subunit A   GO:0003918 DNA topoisomerase type II (ATP-hydrolyzing) activity
DNA topoisomerase VI, subunit A   GO:0006265 DNA topological change
DNA topoisomerase VI, subunit A   GO:0005694 chromosome

1 Parent Features

DB identifier Name Short Name Type
IPR002815 Spo11/DNA topoisomerase VI, subunit A Spo11/TopoVI_A Family

5 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0085657 Q7KPA5 Drosophila melanogaster
FBpp0276684 B5E0G6 Drosophila pseudoobscura
FBpp0169949 B4KME9 Drosophila mojavensis
FBpp0234886 B4LNW4 Drosophila virilis
FBpp0257063 B4PB78 Drosophila yakuba