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Q54RC3 (TOP1_DICDI) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 64. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
DNA topoisomerase 1

EC=5.99.1.2
Alternative name(s):
DNA topoisomerase I
Gene names
Name:top1
ORF Names:DDB_G0283205
OrganismDictyostelium discoideum (Slime mold) [Reference proteome]
Taxonomic identifier44689 [NCBI]
Taxonomic lineageEukaryotaAmoebozoaMycetozoaDictyosteliidaDictyostelium

Protein attributes

Sequence length893 AA.
Sequence statusComplete.
Protein existenceInferred from homology

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 then 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 By similarity.

Catalytic activity

ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.

Subcellular location

Nucleus By similarity.

Miscellaneous

Eukaryotic topoisomerase I and II can relax both negative and positive supercoils, whereas prokaryotic enzymes relax only negative supercoils By similarity.

Sequence similarities

Belongs to the type IB topoisomerase family.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 893893DNA topoisomerase 1
PRO_0000330481

Regions

Region519 – 5202Interaction with DNA By similarity
Region582 – 5876Interaction with DNA By similarity
Region673 – 6753Interaction with DNA By similarity
Compositional bias26 – 316Poly-Thr
Compositional bias92 – 202111Ser-rich
Compositional bias144 – 16522Thr-rich
Compositional bias223 – 27755Thr-rich
Compositional bias284 – 29411Poly-Glu

Sites

Active site8531O-(3'-phospho-DNA)-tyrosine intermediate By similarity
Site4091Interaction with DNA By similarity
Site4571Interaction with DNA By similarity
Site5061Interaction with DNA By similarity
Site5371Interaction with DNA By similarity
Site5941Interaction with DNA By similarity
Site6201Interaction with DNA By similarity
Site6621Interaction with DNA By similarity
Site7211Interaction with DNA By similarity
Site7391Interaction with DNA By similarity

Sequences

Sequence LengthMass (Da)Tools
Q54RC3 [UniParc].

Last modified May 24, 2005. Version 1.
Checksum: DD9BB5F99BF3331E

FASTA893100,612
        10         20         30         40         50         60 
MEVKQEILTP MKVEKTNGNV PTPPPTTTTT TVMDDDLFDD EASPPQPNKK LKAENGSIKK 

        70         80         90        100        110        120 
LTPTPKPAPV TPKPTAAVNG KKPIPKKKPV DSSSDSDSSD SSSDSDSDSS DSDSDSSSSD 

       130        140        150        160        170        180 
SSSSDSDVPK KKPISKIPNK PSGTVSKTSK NSPKTTTTTT TTTTTVKSKP APKVKPEQSS 

       190        200        210        220        230        240 
SDDSSSDSSD DSSDDSSSDS SSEEEKPKKK PSKKPAAVKK EITVKKETTT TTKKTPVKKE 

       250        260        270        280        290        300 
VEVKKETKTT TTKKVKKEES DDDGEDEKTT TKKKTTTRKR KLKEEEEGEE EEEEGVNKWW 

       310        320        330        340        350        360 
DKEDDEDDGT KWTTLIHNGP VFPPAYVPHG IKFMYDGKVV KLTPKQEEVA TFYANYLETD 

       370        380        390        400        410        420 
HVKKQAFKDN FFKEFKGLLT SEQKEIVKKM DKCDFSHIHT HLKTKKEQRK ARSKEEKDAE 

       430        440        450        460        470        480 
TAEKKKIQEK HGFATIDGFK EKVGNYMIEP PGLFLGRGQH PKTGMLKQRI MPSDVTLNIG 

       490        500        510        520        530        540 
EGEVIPPSPI PGEKWKEIVH NNTVTWLAFW RESVNGGFKY VWLAPSSKIK GQADRKKFEV 

       550        560        570        580        590        600 
ARGLKNCIGD IRKGYQKSFN DESTEKRQLA VALYLIDFLA LRVGNEKGED QADTVGCCSL 

       610        620        630        640        650        660 
RVEHIKLESN NTITLDFLGK DSMRYLNTVQ IREDAYKVLK TFVKGKKPTD LLFDSLTVTQ 

       670        680        690        700        710        720 
LNNHLKKQMT GLSAKVFRTY NASITLQKEL DKMDTKEFQS IDEKILFYNR CNREVAILCN 

       730        740        750        760        770        780 
HQKAPPKNLA ETMSKIDEKI QELRDLQDLC RIKIGKTPKS QQEDIESREA ERLPKLIQLA 

       790        800        810        820        830        840 
ITNKKDKDKE KTDKEISFDV KAAFEKSRTL PDAKGKIKEK IAKYEEQIKK QEILKTGKDE 

       850        860        870        880        890 
LKTVALGTSK INYLDPRITV AWCKKNKVPV DKIFTKSLRD KFPWSDVGTD YIF 

« Hide

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AAFI02000051 Genomic DNA. Translation: EAL65841.1.

3D structure databases

ProteinModelPortalQ54RC3.
SMRQ54RC3. Positions 847-885.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING44689.DDBDRAFT_0185416.

Proteomic databases

PRIDEQ54RC3.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblProtistsDDB0234191; DDB0234191; DDB_G0283205.
KEGGddi:DDB_G0283205.

Organism-specific databases

dictyBaseDDB_G0283205. top1.

Phylogenomic databases

eggNOGCOG3569.
KOK03163.
OMADHAKNPT.
PhylomeDBQ54RC3.

Family and domain databases

Gene3D1.10.10.41. 1 hit.
1.10.132.10. 2 hits.
2.170.11.10. 2 hits.
3.90.15.10. 1 hit.
InterProIPR011010. DNA_brk_join_enz.
IPR013034. DNA_topo_domain1.
IPR001631. TopoI.
IPR018521. TopoI_AS.
IPR025834. TopoI_C_dom.
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.
IPR013499. TopoI_euk.
[Graphical view]
PfamPF14370. Topo_C_assoc. 1 hit.
PF01028. Topoisom_I. 1 hit.
PF02919. Topoisom_I_N. 1 hit.
[Graphical view]
PRINTSPR00416. EUTPISMRASEI.
SMARTSM00435. TOPEUc. 1 hit.
[Graphical view]
SUPFAMSSF56349. SSF56349. 2 hits.
SSF56741. SSF56741. 1 hit.
PROSITEPS00176. TOPOISOMERASE_I_EUK. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameTOP1_DICDI
AccessionPrimary (citable) accession number: Q54RC3
Entry history
Integrated into UniProtKB/Swiss-Prot: April 29, 2008
Last sequence update: May 24, 2005
Last modified: April 16, 2014
This is version 64 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)

Relevant documents

SIMILARITY comments

Index of protein domains and families

Dictyostelium discoideum

Dictyostelium discoideum: entries, gene names and cross-references to dictyBase