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Protein

DNA nucleotidylexotransferase

Gene

DNTT

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Template-independent DNA polymerase which catalyzes the random addition of deoxynucleoside 5'-triphosphate to the 3'-end of a DNA initiator. One of the in vivo functions of this enzyme is the addition of nucleotides at the junction (N region) of rearranged Ig heavy chain and T-cell receptor gene segments during the maturation of B- and T-cells.

Catalytic activityi

Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1).

Cofactori

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Metal bindingi253 – 2531Sodium; via carbonyl oxygenBy similarity
Metal bindingi255 – 2551Sodium; via carbonyl oxygenBy similarity
Metal bindingi343 – 3431MagnesiumBy similarity
Metal bindingi345 – 3451MagnesiumBy similarity
Metal bindingi433 – 4331MagnesiumBy similarity

GO - Molecular functioni

  1. DNA binding Source: InterPro
  2. DNA-directed DNA polymerase activity Source: InterPro
  3. DNA nucleotidylexotransferase activity Source: ProtInc
  4. metal ion binding Source: UniProtKB-KW

GO - Biological processi

  1. DNA modification Source: UniProtKB-KW
Complete GO annotation...

Keywords - Molecular functioni

Nucleotidyltransferase, Transferase

Keywords - Biological processi

Terminal addition

Keywords - Ligandi

Magnesium, Metal-binding

Enzyme and pathway databases

SABIO-RKP04053.
SignaLinkiP04053.

Names & Taxonomyi

Protein namesi
Recommended name:
DNA nucleotidylexotransferase (EC:2.7.7.31)
Alternative name(s):
Terminal addition enzyme
Terminal deoxynucleotidyltransferase
Short name:
Terminal transferase
Gene namesi
Name:DNTT
Synonyms:TDT
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 10

Organism-specific databases

HGNCiHGNC:2983. DNTT.

Subcellular locationi

GO - Cellular componenti

  1. cytoplasm Source: HPA
  2. nucleoplasm Source: HPA
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA27449.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 509509DNA nucleotidylexotransferasePRO_0000218791Add
BLAST

Proteomic databases

MaxQBiP04053.
PaxDbiP04053.
PRIDEiP04053.

PTM databases

PhosphoSiteiP04053.

Expressioni

Gene expression databases

BgeeiP04053.
CleanExiHS_DNTT.
GenevestigatoriP04053.

Organism-specific databases

HPAiHPA044194.

Interactioni

Subunit structurei

Interacts with PRP19 and DNTTIP1. Forms a ternary complex with DNTTIP2 and core histone. Released from this complex by PCNA.3 Publications

Protein-protein interaction databases

BioGridi108127. 10 interactions.
IntActiP04053. 1 interaction.
STRINGi9606.ENSP00000360216.

Structurei

Secondary structure

1
509
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi23 – 253Combined sources
Beta strandi36 – 405Combined sources
Turni42 – 443Combined sources
Helixi46 – 5813Combined sources
Beta strandi73 – 786Combined sources
Helixi81 – 9010Combined sources
Beta strandi100 – 1034Combined sources
Helixi104 – 1129Combined sources
Beta strandi120 – 1245Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2COENMR-A19-125[»]
SMRiP04053. Positions 21-125, 149-509.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP04053.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini27 – 12498BRCTPROSITE-ProRule annotationAdd
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni151 – 509359Mediates interaction with DNTTIP2Add
BLAST
Regioni336 – 34510Involved in ssDNA bindingBy similarity

Sequence similaritiesi

Belongs to the DNA polymerase type-X family.Curated
Contains 1 BRCT domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiCOG1796.
GeneTreeiENSGT00530000063002.
HOGENOMiHOG000263600.
HOVERGENiHBG003670.
InParanoidiP04053.
KOiK00977.
OMAiKTWKAIR.
OrthoDBiEOG7BS4BH.
PhylomeDBiP04053.
TreeFamiTF103012.

Family and domain databases

Gene3Di1.10.150.110. 1 hit.
3.30.210.10. 1 hit.
3.40.50.10190. 1 hit.
InterProiIPR001357. BRCT_dom.
IPR002054. DNA-dir_DNA_pol_X.
IPR019843. DNA_pol-X_BS.
IPR010996. DNA_pol_b-like_N.
IPR018944. DNA_pol_lambd_fingers_domain.
IPR022312. DNA_pol_X.
IPR027421. DNA_pol_X_lyase_dom.
IPR002934. Nucleotidyltransferase.
IPR029398. PolB_thumb.
IPR027292. TdT.
IPR001726. TdT/Mu.
[Graphical view]
PfamiPF00533. BRCT. 1 hit.
PF14791. DNA_pol_B_thumb. 1 hit.
PF10391. DNA_pol_lambd_f. 1 hit.
PF01909. NTP_transf_2. 1 hit.
[Graphical view]
PIRSFiPIRSF000817. DNA_NT. 1 hit.
PIRSF501175. TDT. 1 hit.
PRINTSiPR00869. DNAPOLX.
PR00871. DNAPOLXTDT.
SMARTiSM00292. BRCT. 1 hit.
SM00483. POLXc. 1 hit.
[Graphical view]
SUPFAMiSSF47802. SSF47802. 1 hit.
SSF52113. SSF52113. 1 hit.
PROSITEiPS50172. BRCT. 1 hit.
PS00522. DNA_POLYMERASE_X. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: P04053-1) [UniParc]FASTAAdd to basket

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

« Hide

        10         20         30         40         50
MDPPRASHLS PRKKRPRQTG ALMASSPQDI KFQDLVVFIL EKKMGTTRRA
60 70 80 90 100
FLMELARRKG FRVENELSDS VTHIVAENNS GSDVLEWLQA QKVQVSSQPE
110 120 130 140 150
LLDVSWLIEC IRAGKPVEMT GKHQLVVRRD YSDSTNPGPP KTPPIAVQKI
160 170 180 190 200
SQYACQRRTT LNNCNQIFTD AFDILAENCE FRENEDSCVT FMRAASVLKS
210 220 230 240 250
LPFTIISMKD TEGIPCLGSK VKGIIEEIIE DGESSEVKAV LNDERYQSFK
260 270 280 290 300
LFTSVFGVGL KTSEKWFRMG FRTLSKVRSD KSLKFTRMQK AGFLYYEDLV
310 320 330 340 350
SCVTRAEAEA VSVLVKEAVW AFLPDAFVTM TGGFRRGKKM GHDVDFLITS
360 370 380 390 400
PGSTEDEEQL LQKVMNLWEK KGLLLYYDLV ESTFEKLRLP SRKVDALDHF
410 420 430 440 450
QKCFLIFKLP RQRVDSDQSS WQEGKTWKAI RVDLVLCPYE RRAFALLGWT
460 470 480 490 500
GSRQFERDLR RYATHERKMI LDNHALYDKT KRIFLKAESE EEIFAHLGLD

YIEPWERNA
Length:509
Mass (Da):58,536
Last modified:November 2, 2010 - v3
Checksum:i0EC01E380FA7E5A2
GO
Isoform 2 (identifier: P04053-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     454-454: Missing.

Show »
Length:508
Mass (Da):58,408
Checksum:iC72DABE3ACAEADD1
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti51 – 511F → L in BAD97037 (Ref. 4) Curated
Sequence conflicti299 – 2991L → P in BAD97037 (Ref. 4) Curated
Sequence conflicti329 – 3291T → A in BAD97037 (Ref. 4) Curated
Sequence conflicti383 – 3831T → A in BAD97037 (Ref. 4) Curated
Sequence conflicti389 – 3891L → M in BAD97037 (Ref. 4) Curated
Sequence conflicti452 – 4521S → SP in AAA53100 (PubMed:2833741).Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti112 – 1121R → G.5 Publications
Corresponds to variant rs6584066 [ dbSNP | Ensembl ].
VAR_058200

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei454 – 4541Missing in isoform 2. 2 PublicationsVSP_038397

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M11722 mRNA. Translation: AAA36726.1.
M20703
, M22968, M20694, M20695, M20696, M20697, M20698, M20699, M20700, M20701, M20702 mRNA. Translation: AAA53100.1.
AB046378 mRNA. Translation: BAB72001.1.
AK223317 mRNA. Translation: BAD97037.1.
AL136181 Genomic DNA. Translation: CAH72984.1.
BC012920 mRNA. Translation: AAH12920.1.
M21195 Genomic DNA. Translation: AAA61137.1.
K01919 mRNA. Translation: AAA61136.1.
CCDSiCCDS7447.1. [P04053-1]
PIRiA23924. WXHU.
RefSeqiNP_001017520.1. NM_001017520.1. [P04053-2]
NP_004079.3. NM_004088.3. [P04053-1]
UniGeneiHs.534206.

Genome annotation databases

EnsembliENST00000371174; ENSP00000360216; ENSG00000107447. [P04053-1]
GeneIDi1791.
KEGGihsa:1791.
UCSCiuc001kmf.3. human. [P04053-1]
uc001kmg.3. human. [P04053-2]

Polymorphism databases

DMDMi311033533.

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M11722 mRNA. Translation: AAA36726.1.
M20703
, M22968, M20694, M20695, M20696, M20697, M20698, M20699, M20700, M20701, M20702 mRNA. Translation: AAA53100.1.
AB046378 mRNA. Translation: BAB72001.1.
AK223317 mRNA. Translation: BAD97037.1.
AL136181 Genomic DNA. Translation: CAH72984.1.
BC012920 mRNA. Translation: AAH12920.1.
M21195 Genomic DNA. Translation: AAA61137.1.
K01919 mRNA. Translation: AAA61136.1.
CCDSiCCDS7447.1. [P04053-1]
PIRiA23924. WXHU.
RefSeqiNP_001017520.1. NM_001017520.1. [P04053-2]
NP_004079.3. NM_004088.3. [P04053-1]
UniGeneiHs.534206.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2COENMR-A19-125[»]
SMRiP04053. Positions 21-125, 149-509.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi108127. 10 interactions.
IntActiP04053. 1 interaction.
STRINGi9606.ENSP00000360216.

Chemistry

BindingDBiP04053.
ChEMBLiCHEMBL4810.

PTM databases

PhosphoSiteiP04053.

Polymorphism databases

DMDMi311033533.

Proteomic databases

MaxQBiP04053.
PaxDbiP04053.
PRIDEiP04053.

Protocols and materials databases

DNASUi1791.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000371174; ENSP00000360216; ENSG00000107447. [P04053-1]
GeneIDi1791.
KEGGihsa:1791.
UCSCiuc001kmf.3. human. [P04053-1]
uc001kmg.3. human. [P04053-2]

Organism-specific databases

CTDi1791.
GeneCardsiGC10P098072.
H-InvDBHIX0009072.
HGNCiHGNC:2983. DNTT.
HPAiHPA044194.
MIMi187410. gene.
neXtProtiNX_P04053.
PharmGKBiPA27449.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG1796.
GeneTreeiENSGT00530000063002.
HOGENOMiHOG000263600.
HOVERGENiHBG003670.
InParanoidiP04053.
KOiK00977.
OMAiKTWKAIR.
OrthoDBiEOG7BS4BH.
PhylomeDBiP04053.
TreeFamiTF103012.

Enzyme and pathway databases

SABIO-RKP04053.
SignaLinkiP04053.

Miscellaneous databases

EvolutionaryTraceiP04053.
GeneWikiiTerminal_deoxynucleotidyl_transferase.
GenomeRNAii1791.
NextBioi7299.
PROiP04053.
SOURCEiSearch...

Gene expression databases

BgeeiP04053.
CleanExiHS_DNTT.
GenevestigatoriP04053.

Family and domain databases

Gene3Di1.10.150.110. 1 hit.
3.30.210.10. 1 hit.
3.40.50.10190. 1 hit.
InterProiIPR001357. BRCT_dom.
IPR002054. DNA-dir_DNA_pol_X.
IPR019843. DNA_pol-X_BS.
IPR010996. DNA_pol_b-like_N.
IPR018944. DNA_pol_lambd_fingers_domain.
IPR022312. DNA_pol_X.
IPR027421. DNA_pol_X_lyase_dom.
IPR002934. Nucleotidyltransferase.
IPR029398. PolB_thumb.
IPR027292. TdT.
IPR001726. TdT/Mu.
[Graphical view]
PfamiPF00533. BRCT. 1 hit.
PF14791. DNA_pol_B_thumb. 1 hit.
PF10391. DNA_pol_lambd_f. 1 hit.
PF01909. NTP_transf_2. 1 hit.
[Graphical view]
PIRSFiPIRSF000817. DNA_NT. 1 hit.
PIRSF501175. TDT. 1 hit.
PRINTSiPR00869. DNAPOLX.
PR00871. DNAPOLXTDT.
SMARTiSM00292. BRCT. 1 hit.
SM00483. POLXc. 1 hit.
[Graphical view]
SUPFAMiSSF47802. SSF47802. 1 hit.
SSF52113. SSF52113. 1 hit.
PROSITEiPS50172. BRCT. 1 hit.
PS00522. DNA_POLYMERASE_X. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Expression of human terminal deoxynucleotidyl transferase in Escherichia coli."
    Peterson R.C., Cheung L.C., Mattaliano R.J., White S.T., Chang L.M.S., Bollum F.J.
    J. Biol. Chem. 260:10495-10502(1984) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2), VARIANT GLY-112.
  2. "Human terminal deoxyribonucleotidyltransferase: molecular cloning and structural analysis of the gene and 5' flanking region."
    Riley L.K., Morrow J.K., Danton M.J., Coleman M.S.
    Proc. Natl. Acad. Sci. U.S.A. 85:2489-2493(1987) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), VARIANT GLY-112.
  3. "Terminal deoxynucleotidyltransferase is negatively regulated by direct interaction with proliferating cell nuclear antigen."
    Ibe S., Fujita K., Toyomoto T., Shimazaki N., Kaneko R., Tanabe A., Takebe I., Kuroda S., Kobayashi T., Toji S., Tamai K., Yamamoto H., Koiwai O.
    Genes Cells 6:815-824(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), VARIANT GLY-112.
  4. Suzuki Y., Sugano S., Totoki Y., Toyoda A., Takeda T., Sakaki Y., Tanaka A., Yokoyama S.
    Submitted (MAR-2005) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANT GLY-112.
    Tissue: Thymus.
  5. "The DNA sequence and comparative analysis of human chromosome 10."
    Deloukas P., Earthrowl M.E., Grafham D.V., Rubenfield M., French L., Steward C.A., Sims S.K., Jones M.C., Searle S., Scott C., Howe K., Hunt S.E., Andrews T.D., Gilbert J.G.R., Swarbreck D., Ashurst J.L., Taylor A., Battles J.
    , Bird C.P., Ainscough R., Almeida J.P., Ashwell R.I.S., Ambrose K.D., Babbage A.K., Bagguley C.L., Bailey J., Banerjee R., Bates K., Beasley H., Bray-Allen S., Brown A.J., Brown J.Y., Burford D.C., Burrill W., Burton J., Cahill P., Camire D., Carter N.P., Chapman J.C., Clark S.Y., Clarke G., Clee C.M., Clegg S., Corby N., Coulson A., Dhami P., Dutta I., Dunn M., Faulkner L., Frankish A., Frankland J.A., Garner P., Garnett J., Gribble S., Griffiths C., Grocock R., Gustafson E., Hammond S., Harley J.L., Hart E., Heath P.D., Ho T.P., Hopkins B., Horne J., Howden P.J., Huckle E., Hynds C., Johnson C., Johnson D., Kana A., Kay M., Kimberley A.M., Kershaw J.K., Kokkinaki M., Laird G.K., Lawlor S., Lee H.M., Leongamornlert D.A., Laird G., Lloyd C., Lloyd D.M., Loveland J., Lovell J., McLaren S., McLay K.E., McMurray A., Mashreghi-Mohammadi M., Matthews L., Milne S., Nickerson T., Nguyen M., Overton-Larty E., Palmer S.A., Pearce A.V., Peck A.I., Pelan S., Phillimore B., Porter K., Rice C.M., Rogosin A., Ross M.T., Sarafidou T., Sehra H.K., Shownkeen R., Skuce C.D., Smith M., Standring L., Sycamore N., Tester J., Thorpe A., Torcasso W., Tracey A., Tromans A., Tsolas J., Wall M., Walsh J., Wang H., Weinstock K., West A.P., Willey D.L., Whitehead S.L., Wilming L., Wray P.W., Young L., Chen Y., Lovering R.C., Moschonas N.K., Siebert R., Fechtel K., Bentley D., Durbin R.M., Hubbard T., Doucette-Stamm L., Beck S., Smith D.R., Rogers J.
    Nature 429:375-381(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  6. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
    The MGC Project Team
    Genome Res. 14:2121-2127(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1), VARIANT GLY-112.
    Tissue: Testis.
  7. "Isolation of putative promoter region for human terminal deoxynucleotidyltransferase gene."
    Koiwai O., Morita A.
    Biochem. Biophys. Res. Commun. 154:91-100(1987) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-67.
  8. Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 271-508 (ISOFORM 2).
  9. "Terminal deoxynucleotidyltransferase directly interacts with a novel nuclear protein that is homologous to p65."
    Yamashita N., Shimazaki N., Ibe S., Kaneko R., Tanabe A., Toyomoto T., Fujita K., Hasegawa T., Toji S., Tamai K., Yamamoto H., Koiwai O.
    Genes Cells 6:641-652(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: INTERACTION WITH DNTTIP1.
    Tissue: Thymus.
  10. "Terminal deoxynucleotidyltransferase forms a ternary complex with a novel chromatin remodeling protein with 82 kDa and core histone."
    Fujita K., Shimazaki N., Ohta Y., Kubota T., Ibe S., Toji S., Tamai K., Fujisaki S., Hayano T., Koiwai O.
    Genes Cells 8:559-571(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: INTERACTION WITH DNTTIP2 AND CORE HISTONE.
  11. "Role of human Pso4 in mammalian DNA repair and association with terminal deoxynucleotidyl transferase."
    Mahajan K.N., Mitchell B.S.
    Proc. Natl. Acad. Sci. U.S.A. 100:10746-10751(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: INTERACTION WITH PRP19.
  12. "Mutational analysis of residues in the nucleotide binding domain of human terminal deoxynucleotidyl transferase."
    Yang B., Gathy K.N., Coleman M.S.
    J. Biol. Chem. 269:11859-11868(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS.
  13. "Solution structure of BRCT domain of terminal deoxynucleotidyltransferase."
    RIKEN structural genomics initiative (RSGI)
    Submitted (OCT-2005) to the PDB data bank
    Cited for: STRUCTURE BY NMR OF 19-125.

Entry informationi

Entry nameiTDT_HUMAN
AccessioniPrimary (citable) accession number: P04053
Secondary accession number(s): Q53FH1, Q5W103, Q96E50
Entry historyi
Integrated into UniProtKB/Swiss-Prot: November 1, 1986
Last sequence update: November 2, 2010
Last modified: April 1, 2015
This is version 167 of the entry and version 3 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 10
    Human chromosome 10: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. SIMILARITY comments
    Index of protein domains and families

External Data

Dasty 3

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into Uniref entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.