P93119 (TOP1_DAUCA) 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

Daucus carota (Carrot)

Taxonomic identifier

4039 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › campanulids › Apiales › Apiaceae › Apioideae › Scandiceae › Daucinae › Daucus

Protein attributes

Sequence length	790 AA.
Sequence status	Complete.
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 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.
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
Gene Ontology (GO)
Biological process	DNA topological change Inferred from electronic annotation. Source: InterPro
Cellular component	chromosome Inferred from electronic annotation. Source: InterPro nucleus Inferred from electronic annotation. Source: UniProtKB-SubCell
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 electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 790	790	DNA topoisomerase 1		PRO_0000145207
Sites
	Active site	749	1	O-(3'-phospho-DNA)-tyrosine intermediate By similarity

Sequences

	Sequence		Length	Mass (Da)
	P93119 [UniParc]. Last modified May 1, 1997. Version 1. Checksum: CE1D7DA3FF3291F5	FASTA	790	89,771
	10 20 30 40 50 60 MKSNPGITVI KQNASNVMEK TLKEEGQSRS NSEDSDDDKP LSHKLSSGAL NGNSHHIRMG 70 80 90 100 110 120 SNLSCPSPYT SPKPRIIKGP EDEMLLSSEL QLNAGASNAE SSDSDESKPL ASELEDPSSS 130 140 150 160 170 180 LNKRPLIQPK NSDPSPSKKA KLSEPSAPTN RKLKTAEQEE AAADDDPSIS NRNKKSTTPA 190 200 210 220 230 240 SKVSDKKKRP DVSASVNKVD FSKSLKVPLV LVKGRNGQPL VHNGVIFPPL YKPHGVKMLY 250 260 270 280 290 300 RENPVDLTPE QEEVATMFAV MLETEYMTKP KFRENFMSDW RKILGEKHII QNLEDCDFTP 310 320 330 340 350 360 IYEWHQREKE KKKQMSTDEK KAIKEGKDET RKEKYMWAVV DGMSREKVGN FRVGTTRVVQ 370 380 390 400 410 420 RSWRASKDPQ VKKNVYSQID ITINIGKDAP IPEPPIPGER WKEIRHDNTV TWLAFWNDPI 430 440 450 460 470 480 NPKEFKYVFL AASSSLKGKV TREKYEKSRK LKDYIEGIRA AAYTKDFASK DSKKRQIAVA 490 500 510 520 530 540 TYLIDKLALR AGNEKDDDEA DTVGCCTLKV ENVETKRPNI LKFDFLGKDS IRYQNEVEVE 550 560 570 580 590 600 PRVFSAIEQF RSGKEGGDDL FDQLDTSKLN AHLKELMPGL TAKVFRTYNA SITLDEMVRC 610 620 630 640 650 660 KLLSRETKGG DVAEKVVVYQ HANKEVAIIC NHQRTVSKSH SAQMVRLNEK IEELKGLLKE 670 680 690 700 710 720 LQEDLTRVNK GKPPLKNSDG KPKRNLNLKR YKGKLLKLIQ KLRKWSETRR LSVTKKIAQT 730 740 750 760 770 780 NTKIEKMERD KETKEDLKTV ALGTSKINYL DPRITVAWCK RHDVPIEKIF NKSLLAKFAW 790 AMDVVLIFRF

References

[1]	"Cloning of a cDNA encoding DNA topoisomerase I in Daucus carota and expression analysis in relation to cell proliferation." Balestrazzi A., Toscano I., Bernacchia G., Luo M., Otte S., Carbonera D. Gene 183:183-190(1996) [PubMed: 8996105] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Lunga di Amsterdam.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	U60440 mRNA. Translation: AAB41401.1.
PIR	JC5749.
3D structure databases
ProteinModelPortal	P93119.
SMR	P93119. Positions 218-635, 734-784.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
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. [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. 1 hit.
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. SSF56741. TopoI_DNA_bd_euk. 1 hit.
PROSITE	PS00176. TOPOISOMERASE_I_EUK. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

TOP1_DAUCA

Accession

Primary (citable) accession number: P93119

Entry history

Integrated into UniProtKB/Swiss-Prot:	June 1, 2001
Last sequence update:	May 1, 1997
Last modified:	November 16, 2011
This is version 65 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program