The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:

"
Topoisomerase I, domain 3
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
« Back to all FunFams

FunFam 1: DNA topoisomerase

Please note: GO annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

There are 14 GO terms relating to "molecular function"

The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.
GO Term Annotations Evidence
Protein binding GO:0005515
Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).
7 O60126 (/IPI) O95985 (/IPI) O95985 (/IPI) O95985 (/IPI) P13099 (/IPI) P13099 (/IPI) Q13472 (/IPI)
DNA topoisomerase type I activity GO:0003917
Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.
6 O61660 (/IDA) O96651 (/IDA) O96651 (/IDA) P13099 (/IDA) P13099 (/IDA) Q13472 (/IDA)
DNA binding GO:0003677
Any molecular function by which a gene product interacts selectively and non-covalently with DNA (deoxyribonucleic acid).
5 O60126 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM)
DNA binding GO:0003677
Any molecular function by which a gene product interacts selectively and non-covalently with DNA (deoxyribonucleic acid).
4 O95985 (/TAS) O95985 (/TAS) O95985 (/TAS) Q13472 (/TAS)
DNA topoisomerase type I activity GO:0003917
Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.
4 Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM)
RNA binding GO:0003723
Interacting selectively and non-covalently with an RNA molecule or a portion thereof.
3 O95985 (/HDA) O95985 (/HDA) O95985 (/HDA)
DNA topoisomerase activity GO:0003916
Catalysis of the transient cleavage and passage of individual DNA strands or double helices through one another, resulting a topological transformation in double-stranded DNA.
3 P13099 (/IDA) P13099 (/IDA) Q9NG98 (/IDA)
DNA topoisomerase activity GO:0003916
Catalysis of the transient cleavage and passage of individual DNA strands or double helices through one another, resulting a topological transformation in double-stranded DNA.
3 O95985 (/TAS) O95985 (/TAS) O95985 (/TAS)
Single-stranded DNA binding GO:0003697
Interacting selectively and non-covalently with single-stranded DNA.
2 O70157 (/ISO) O70157 (/ISO)
MRNA binding GO:0003729
Interacting selectively and non-covalently with messenger RNA (mRNA), an intermediate molecule between DNA and protein. mRNA includes UTR and coding sequences, but does not contain introns.
2 F4ISQ7 (/IDA) F4ISQ7 (/IDA)
DNA topoisomerase type I activity GO:0003917
Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.
2 O70157 (/ISO) O70157 (/ISO)
DNA topoisomerase type I activity GO:0003917
Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.
2 O70157 (/ISS) O70157 (/ISS)
Single-stranded DNA binding GO:0003697
Interacting selectively and non-covalently with single-stranded DNA.
1 Q13472 (/IDA)
DNA topoisomerase type I activity GO:0003917
Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.
1 O60126 (/TAS)

There are 32 GO terms relating to "biological process"

The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.
GO Term Annotations Evidence
DNA topological change GO:0006265
The process in which a transformation is induced in the topological structure of a double-stranded DNA helix, resulting in a change in linking number.
6 O61660 (/IDA) O96651 (/IDA) O96651 (/IDA) P13099 (/IDA) P13099 (/IDA) Q13472 (/IDA)
DNA topological change GO:0006265
The process in which a transformation is induced in the topological structure of a double-stranded DNA helix, resulting in a change in linking number.
4 Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM)
DNA unwinding involved in DNA replication GO:0006268
The process in which interchain hydrogen bonds between two strands of DNA are broken or 'melted', generating unpaired template strands for DNA replication.
4 Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM)
DNA modification GO:0006304
The covalent alteration of one or more nucleotide sites in DNA, resulting in a change in its properties.
4 Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM) Q384B1 (/ISM)
Chromosome segregation GO:0007059
The process in which genetic material, in the form of chromosomes, is organized into specific structures and then physically separated and apportioned to two or more sets. In eukaryotes, chromosome segregation begins with the condensation of chromosomes, includes chromosome separation, and ends when chromosomes have completed movement to the spindle poles.
3 Q9LVP1 (/IMP) Q9Z321 (/IMP) Q9Z321 (/IMP)
Regulation of DNA recombination GO:0000018
Any process that modulates the frequency, rate or extent of DNA recombination, a DNA metabolic process in which a new genotype is formed by reassortment of genes resulting in gene combinations different from those that were present in the parents.
2 P13099 (/IMP) P13099 (/IMP)
DNA topological change GO:0006265
The process in which a transformation is induced in the topological structure of a double-stranded DNA helix, resulting in a change in linking number.
2 O70157 (/ISO) O70157 (/ISO)
DNA topological change GO:0006265
The process in which a transformation is induced in the topological structure of a double-stranded DNA helix, resulting in a change in linking number.
2 O70157 (/ISS) O70157 (/ISS)
Telomere maintenance via telomerase GO:0007004
The maintenance of proper telomeric length by the addition of telomeric repeats by telomerase.
2 P13099 (/IMP) P13099 (/IMP)
Mitotic sister chromatid cohesion GO:0007064
The cell cycle process in which the sister chromatids of a replicated chromosome are joined along the entire length of the chromosome, from their formation in S phase through metaphase during a mitotic cell cycle. This cohesion cycle is critical for high fidelity chromosome transmission.
2 P13099 (/IMP) P13099 (/IMP)
Reciprocal meiotic recombination GO:0007131
The cell cycle process in which double strand breaks are formed and repaired through a double Holliday junction intermediate. This results in the equal exchange of genetic material between non-sister chromatids in a pair of homologous chromosomes. These reciprocal recombinant products ensure the proper segregation of homologous chromosomes during meiosis I and create genetic diversity.
2 P13099 (/IMP) P13099 (/IMP)
Mitochondrial DNA metabolic process GO:0032042
The chemical reactions and pathways involving mitochondrial DNA.
2 O70157 (/ISO) O70157 (/ISO)
Chromosome separation GO:0051304
The cell cycle process in which paired chromosomes are detached from each other. Chromosome separation begins with the release of cohesin complexes from chromosomes; in budding yeast, this includes the cleavage of cohesin complexes along the chromosome arms, followed by the separation of the centromeric regions. Chromosome separation also includes formation of chromatid axes mediated by condensins, and ends with the disentangling of inter-sister catenation catalyzed by topoisomerase II (topo II).
2 O70157 (/ISO) O70157 (/ISO)
Chromosome separation GO:0051304
The cell cycle process in which paired chromosomes are detached from each other. Chromosome separation begins with the release of cohesin complexes from chromosomes; in budding yeast, this includes the cleavage of cohesin complexes along the chromosome arms, followed by the separation of the centromeric regions. Chromosome separation also includes formation of chromatid axes mediated by condensins, and ends with the disentangling of inter-sister catenation catalyzed by topoisomerase II (topo II).
2 O70157 (/ISS) O70157 (/ISS)
Positive regulation of synapse assembly GO:0051965
Any process that activates, maintains or increases the frequency, rate or extent of synapse assembly, the aggregation, arrangement and bonding together of a set of components to form a synapse.
2 O96651 (/IMP) O96651 (/IMP)
Mitochondrial genome maintenance GO:0000002
The maintenance of the structure and integrity of the mitochondrial genome; includes replication and segregation of the mitochondrial chromosome.
1 Q9NG98 (/IMP)
Mitotic cell cycle GO:0000278
Progression through the phases of the mitotic cell cycle, the most common eukaryotic cell cycle, which canonically comprises four successive phases called G1, S, G2, and M and includes replication of the genome and the subsequent segregation of chromosomes into daughter cells. In some variant cell cycles nuclear replication or nuclear division may not be followed by cell division, or G1 and G2 phases may be absent.
1 Q9LVP1 (/IMP)
Resolution of meiotic recombination intermediates GO:0000712
The cleavage and rejoining of intermediates, such as Holliday junctions, formed during meiotic recombination to produce two intact molecules in which genetic material has been exchanged.
1 Q9LVP1 (/IMP)
Resolution of meiotic recombination intermediates GO:0000712
The cleavage and rejoining of intermediates, such as Holliday junctions, formed during meiotic recombination to produce two intact molecules in which genetic material has been exchanged.
1 O60126 (/TAS)
Double-strand break repair via homologous recombination GO:0000724
The error-free repair of a double-strand break in DNA in which the broken DNA molecule is repaired using homologous sequences. A strand in the broken DNA searches for a homologous region in an intact chromosome to serve as the template for DNA synthesis. The restoration of two intact DNA molecules results in the exchange, reciprocal or nonreciprocal, of genetic material between the intact DNA molecule and the broken DNA molecule.
1 Q9NG98 (/IMP)
DNA replication GO:0006260
The cellular metabolic process in which a cell duplicates one or more molecules of DNA. DNA replication begins when specific sequences, known as origins of replication, are recognized and bound by initiation proteins, and ends when the original DNA molecule has been completely duplicated and the copies topologically separated. The unit of replication usually corresponds to the genome of the cell, an organelle, or a virus. The template for replication can either be an existing DNA molecule or RNA.
1 Q13472 (/TAS)
DNA repair GO:0006281
The process of restoring DNA after damage. Genomes are subject to damage by chemical and physical agents in the environment (e.g. UV and ionizing radiations, chemical mutagens, fungal and bacterial toxins, etc.) and by free radicals or alkylating agents endogenously generated in metabolism. DNA is also damaged because of errors during its replication. A variety of different DNA repair pathways have been reported that include direct reversal, base excision repair, nucleotide excision repair, photoreactivation, bypass, double-strand break repair pathway, and mismatch repair pathway.
1 Q9LVP1 (/IMP)
Postreplication repair GO:0006301
The conversion of DNA-damage induced single-stranded gaps into large molecular weight DNA after replication. Includes pathways that remove replication-blocking lesions in conjunction with DNA replication.
1 O60126 (/IGI)
Mitochondrial DNA metabolic process GO:0032042
The chemical reactions and pathways involving mitochondrial DNA.
1 Q13472 (/IMP)
Tissue regeneration GO:0042246
The regrowth of lost or destroyed tissues.
1 Q9NG98 (/IMP)
Maintenance of rDNA GO:0043007
Any process involved in sustaining the fidelity and copy number of rDNA repeats.
1 O60126 (/IMP)
Developmental growth GO:0048589
The increase in size or mass of an entire organism, a part of an organism or a cell, where the increase in size or mass has the specific outcome of the progression of the organism over time from one condition to another.
1 Q9NG98 (/IMP)
Chromosome separation GO:0051304
The cell cycle process in which paired chromosomes are detached from each other. Chromosome separation begins with the release of cohesin complexes from chromosomes; in budding yeast, this includes the cleavage of cohesin complexes along the chromosome arms, followed by the separation of the centromeric regions. Chromosome separation also includes formation of chromatid axes mediated by condensins, and ends with the disentangling of inter-sister catenation catalyzed by topoisomerase II (topo II).
1 Q13472 (/IMP)
Meiotic cell cycle GO:0051321
Progression through the phases of the meiotic cell cycle, in which canonically a cell replicates to produce four offspring with half the chromosomal content of the progenitor cell via two nuclear divisions.
1 Q9LVP1 (/IMP)
Meiotic cell cycle GO:0051321
Progression through the phases of the meiotic cell cycle, in which canonically a cell replicates to produce four offspring with half the chromosomal content of the progenitor cell via two nuclear divisions.
1 Q13472 (/TAS)
Regulation of signal transduction by p53 class mediator GO:1901796
Any process that modulates the frequency, rate or extent of signal transduction by p53 class mediator.
1 Q13472 (/TAS)
Mitotic DNA replication GO:1902969
Any nuclear DNA replication that is involved in a mitotic cell cycle.
1 O60126 (/IMP)

There are 14 GO terms relating to "cellular component"

The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.
GO Term Annotations Evidence
Nucleus GO:0005634
A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.
4 O95985 (/TAS) O95985 (/TAS) O95985 (/TAS) Q13472 (/TAS)
Cytoplasm GO:0005737
All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.
4 Q384B1 (/IDA) Q384B1 (/IDA) Q384B1 (/IDA) Q384B1 (/IDA)
Nucleoplasm GO:0005654
That part of the nuclear content other than the chromosomes or the nucleolus.
3 O70157 (/TAS) O70157 (/TAS) Q13472 (/TAS)
RecQ helicase-Topo III complex GO:0031422
A complex containing a RecQ family helicase and a topoisomerase III homologue; may also include one or more additional proteins; conserved from E. coli to human.
3 O60126 (/IDA) P13099 (/IDA) P13099 (/IDA)
Condensed chromosome GO:0000793
A highly compacted molecule of DNA and associated proteins resulting in a cytologically distinct structure.
2 Q9Z321 (/IDA) Q9Z321 (/IDA)
Nucleus GO:0005634
A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.
2 P13099 (/IC) P13099 (/IC)
Nucleus GO:0005634
A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.
2 O60126 (/IDA) Q9NG98 (/IDA)
PML body GO:0016605
A class of nuclear body; they react against SP100 auto-antibodies (PML, promyelocytic leukemia); cells typically contain 10-30 PML bodies per nucleus; alterations in the localization of PML bodies occurs after viral infection.
2 O70157 (/ISO) O70157 (/ISO)
RecQ helicase-Topo III complex GO:0031422
A complex containing a RecQ family helicase and a topoisomerase III homologue; may also include one or more additional proteins; conserved from E. coli to human.
2 P13099 (/IPI) P13099 (/IPI)
Cytoplasm GO:0005737
All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.
1 Q4Q888 (/ISO)
Mitochondrion GO:0005739
A semiautonomous, self replicating organelle that occurs in varying numbers, shapes, and sizes in the cytoplasm of virtually all eukaryotic cells. It is notably the site of tissue respiration.
1 O60126 (/HDA)
Mitochondrion GO:0005739
A semiautonomous, self replicating organelle that occurs in varying numbers, shapes, and sizes in the cytoplasm of virtually all eukaryotic cells. It is notably the site of tissue respiration.
1 Q9NG98 (/IDA)
PML body GO:0016605
A class of nuclear body; they react against SP100 auto-antibodies (PML, promyelocytic leukemia); cells typically contain 10-30 PML bodies per nucleus; alterations in the localization of PML bodies occurs after viral infection.
1 Q13472 (/IDA)
Site of double-strand break GO:0035861
A region of a chromosome at which a DNA double-strand break has occurred. DNA damage signaling and repair proteins accumulate at the lesion to respond to the damage and repair the DNA to form a continuous DNA helix.
1 O60126 (/IDA)