Q7YR26 (TOP1_CHLAE) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
DNA topoisomerase 1
EC=5.99.1.2

Alternative name(s):
DNA topoisomerase I

Gene names

Name:

TOP1

Organism

Chlorocebus aethiops (Green monkey) (Cercopithecus aethiops)

Taxonomic identifier

9534 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Cercopithecidae › Cercopithecinae › Chlorocebus

Protein attributes

Sequence length	767 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 5'-OH DNA strand. The free DNA strand than undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 5'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone. Regulates the alternative splicing of tissue factor (F3) pre-mRNA in endothelial cells By similarity.
Catalytic activity	ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.
Enzyme regulation	Specifically inhibited by camptothecin (CPT), a plant alkaloid with antitumor activity.
Subunit structure	Monomer By similarity.
Subcellular location	Nucleus › nucleolus. Nucleus › nucleoplasm. Note: Diffuse nuclear localization with some enrichment in nucleoli. On CPT treatment, cleared from nucleoli into nucleoplasm. Sumolyated forms found in both nucleoplasm and nucleoli By similarity.
Post-translational modification	Sumoylated. Lys-119 is the main site of sumoylation. Sumoylation plays a role in partitioning TOP1 between nucleoli and nucleoplasm. Levels are dramatically increased on camptothecin (CPT) treatment By similarity.
Miscellaneous	Eukaryotic topoisomerase I and II can relax both negative and positive supercoils, whereas prokaryotic enzymes relax only negative supercoils.
Sequence similarities	Belongs to the type IB topoisomerase family.

Ontologies

Keywords
Cellular component	Nucleus
Ligand	ATP-binding DNA-binding Nucleotide-binding
Molecular function	Isomerase Topoisomerase
PTM	Acetylation Isopeptide bond Phosphoprotein Ubl conjugation
Gene Ontology (GO)
Biological process	DNA topological change Inferred from electronic annotation. Source: InterPro
Cellular component	chromosome Inferred from electronic annotation. Source: InterPro nucleolus Inferred from sequence or structural similarity. Source: UniProtKB nucleoplasm Inferred from sequence or structural similarity. Source: UniProtKB
Molecular function	ATP binding Inferred from electronic annotation. Source: UniProtKB-KW DNA topoisomerase (ATP-hydrolyzing) activity Inferred from electronic annotation. Source: InterPro DNA topoisomerase type I activity Inferred from sequence or structural similarity. Source: UniProtKB chromatin binding Inferred from sequence or structural similarity. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed By similarity
	Chain	2 – 767	766	DNA topoisomerase 1		PRO_0000145199
Regions
	Compositional bias	23 – 206	184	Lys-rich
Sites
	Active site	725	1	O-(3'-phospho-DNA)-tyrosine intermediate By similarity
Amino acid modifications
	Modified residue	2	1	N-acetylserine By similarity
	Modified residue	114	1	Phosphoserine By similarity
	Modified residue	282	1	N6-acetyllysine By similarity
	Cross-link	105		Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SUMO) Probable
	Cross-link	119		Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SUMO) By similarity
	Cross-link	155		Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SUMO) Probable

Sequences

	Sequence		Length	Mass (Da)
	Q7YR26 [UniParc]. Last modified October 1, 2003. Version 1. Checksum: 3E6B4B6738923A5D	FASTA	767	90,954
	10 20 30 40 50 60 MSGDHLHNDS QIEADFRLND SHKHKDKHKD REHRHKEHKK DKEKDREKSK HSNSEHKDSE 70 80 90 100 110 120 KKHKEKEKTK HKDGSSEKHK DKHKDRDKEK RKEEKVRASG DAKIKKEKEN GFSSPPQIKD 130 140 150 160 170 180 EPEDDGYFVP PKEDIKPLKR PRDEDDADYK PKKIKTEDIK KEKKRKLEEE EDGKLRKPKN 190 200 210 220 230 240 KDKDKKVPEP DNKKKKPKKE EEQKWKWWEE ERYPEGIKWK FLEHKGPVFA PPYEPLPDSV 250 260 270 280 290 300 KFYYDGKVMK LSPKAEEVAT FFAKMLDHEY TTKEIFRKNF FKDWRKEMTN EEKNIITNLS 310 320 330 340 350 360 KCDFTQMSQY FKAQTEARKQ MSKEEKLKIK EENEKLLKEY GFCIMDNHKE RIANFKIEPP 370 380 390 400 410 420 GLFRGRGNHP KMGMLKRRIM PEDIIINCSK DAKVPSPPPG HKWKEVRHDN KVTWLVSWTE 430 440 450 460 470 480 NIQGSIKYIM LNPSSRIKGE KDWQKYETAR RLKKCVDKIR NQYREDWKSK EMKVRQRAVA 490 500 510 520 530 540 LYFIDKLALR AGNEKEEGET ADTVGCCSLR VEHINLHPEL DGQEYVVEFD FLGKDSIRYY 550 560 570 580 590 600 NKVPVEKRVF KNLQLFMENK QPEDDLFDRL NTGILNKHLQ DLMEGLTAKV FRTYNASITL 610 620 630 640 650 660 QQQLKELTAP DENIPAKILS YNRANRAVAI LCNHQRAPPK TFEKSMMNLQ SKIDAKKEQL 670 680 690 700 710 720 ADARRDLKSA KADAKVMKDA KTKKVVESKK KAVQRLEEQL MKLEVQATDR EENKQIALGT 730 740 750 760 SKLNYLDPRI TVAWCKKWGV PIEKIYNKTQ REKFAWAIDM ADEDYEF

References

[1]

"Human topoisomerase I promotes HIV-1 proviral DNA synthesis: Implications for the species specificity and cellular tropism of HIV-1 infection." Shoya Y., Tokunaga K., Sawa H., Maeda M., Ueno T., Yoshikawa T., Hasegawa H., Sata T., Kurata T., Hall W.W., Cullen B.R., Takahashi H. Proc. Natl. Acad. Sci. U.S.A. 100:8442-8447(2003) [PubMed: 12829794] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	AB089321 mRNA. Translation: BAC78678.1.
3D structure databases
ProteinModelPortal	Q7YR26.
SMR	Q7YR26. Positions 201-767.
ModBase	Search...
Proteomic databases
PRIDE	Q7YR26.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Phylogenomic databases
HOVERGEN	HBG007988.
Family and domain databases
InterPro	IPR011010. DNA_brk_join_enz. IPR013034. DNA_topo_domain1. IPR018521. TopoI_AS. IPR001631. TopoI_C. IPR013499. TopoI_C_euk. IPR014711. TopoI_cat_a-hlx-sub_euk. IPR014727. TopoI_cat_a/b-sub_euk. IPR013500. TopoI_cat_euk. IPR008336. TopoI_DNA-bd_euk. IPR013030. TopoI_DNA-bd_mixed-a/b_euk. IPR009054. TopoI_insert_euk. [Graphical view]
Gene3D	G3DSA:3.90.15.10. TopoI_cat_a-hlx-sub_euk. 1 hit. G3DSA:1.10.132.10. TopoI_cat_a/b-sub_euk. 1 hit. G3DSA:1.10.10.41. TopoI_DNA-bd_a-hlx_euk. 1 hit. G3DSA:2.170.11.10. TopoI_DNA-bd_mixed-a/b_euk. 2 hits.
Pfam	PF01028. Topoisom_I. 1 hit. PF02919. Topoisom_I_N. 1 hit. [Graphical view]
PRINTS	PR00416. EUTPISMRASEI.
SMART	SM00435. TOPEUc. 1 hit. [Graphical view]
SUPFAM	SSF56349. DNA_brk_join_enz. 1 hit. SSF46596. Topismrse_insert. 1 hit. SSF56741. TopoI_DNA_bd_euk. 1 hit.
PROSITE	PS00176. TOPOISOMERASE_I_EUK. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

TOP1_CHLAE

Accession

Primary (citable) accession number: Q7YR26

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 21, 2003
Last sequence update:	October 1, 2003
Last modified:	November 16, 2011
This is version 56 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program