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Protein

DNA polymerase epsilon subunit 2

Gene

POLE2

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

Functioni

Participates in DNA repair and in chromosomal DNA replication.

Catalytic activityi

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

GO - Molecular functioni

  • DNA binding Source: UniProtKB-KW
  • DNA-directed DNA polymerase activity Source: ProtInc

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

DNA-directed DNA polymerase, Nucleotidyltransferase, Transferase

Keywords - Biological processi

DNA replication

Keywords - Ligandi

DNA-binding

Enzyme and pathway databases

ReactomeiREACT_1095. Activation of the pre-replicative complex.
REACT_1993. Repair synthesis for gap-filling by DNA polymerase in TC-NER.
REACT_2244. DNA replication initiation.
REACT_355250. Termination of translesion DNA synthesis.
REACT_355480. Recognition of DNA damage by PCNA-containing replication complex.
REACT_355510. PCNA-Dependent Long Patch Base Excision Repair.
REACT_378. Repair synthesis of patch ~27-30 bases long by DNA polymerase.
REACT_7993. Telomere C-strand synthesis initiation.

Names & Taxonomyi

Protein namesi
Recommended name:
DNA polymerase epsilon subunit 2 (EC:2.7.7.7)
Alternative name(s):
DNA polymerase II subunit 2
DNA polymerase epsilon subunit B
Gene namesi
Name:POLE2
Synonyms:DPE2
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 14

Organism-specific databases

HGNCiHGNC:9178. POLE2.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA278.

Chemistry

DrugBankiDB00242. Cladribine.

Polymorphism and mutation databases

BioMutaiPOLE2.
DMDMi3915676.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 527527DNA polymerase epsilon subunit 2PRO_0000071562Add
BLAST

Proteomic databases

MaxQBiP56282.
PaxDbiP56282.
PRIDEiP56282.

PTM databases

PhosphoSiteiP56282.

Expressioni

Gene expression databases

BgeeiP56282.
CleanExiHS_POLE2.
ExpressionAtlasiP56282. baseline and differential.
GenevestigatoriP56282.

Organism-specific databases

HPAiHPA027555.

Interactioni

Subunit structurei

Component of the epsilon DNA polymerase complex consisting of four subunits: POLE, POLE2, POLE3 and POLE4.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
AGFG1P525943EBI-713847,EBI-996560
HEL-S-30V9HWB83EBI-713847,EBI-10215395
MAPRE1Q156913EBI-713847,EBI-1004115
RELQ048643EBI-713847,EBI-307352
TBX15Q96SF73EBI-713847,EBI-10191361
TRIM27P143733EBI-713847,EBI-719493

Protein-protein interaction databases

BioGridi111423. 26 interactions.
IntActiP56282. 13 interactions.
MINTiMINT-1377461.
STRINGi9606.ENSP00000216367.

Structurei

Secondary structure

1
527
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi3 – 1614Combined sources
Helixi23 – 3210Combined sources
Turni33 – 353Combined sources
Turni38 – 403Combined sources
Helixi41 – 5212Combined sources
Beta strandi58 – 625Combined sources
Helixi64 – 7310Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2V6ZNMR-M1-73[»]
ProteinModelPortaliP56282.
SMRiP56282. Positions 1-75.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP56282.

Family & Domainsi

Sequence similaritiesi

Phylogenomic databases

eggNOGiNOG311342.
GeneTreeiENSGT00390000012435.
HOGENOMiHOG000265254.
HOVERGENiHBG061290.
InParanoidiP56282.
KOiK02325.
OMAiILQQRTH.
OrthoDBiEOG725DH7.
PhylomeDBiP56282.
TreeFamiTF103007.

Family and domain databases

InterProiIPR007185. DNA_pol_alpha/epsilon_bsu.
IPR016266. DNA_pol_e_bsu.
IPR024639. DNA_pol_e_bsu_N.
[Graphical view]
PfamiPF04042. DNA_pol_E_B. 1 hit.
PF12213. Dpoe2NT. 1 hit.
[Graphical view]
PIRSFiPIRSF000799. DNA_pol_eps_2. 1 hit.

Sequences (3)i

Sequence statusi: Complete.

This entry describes 3 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: P56282-1) [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
MAPERLRSRA LSAFKLRGLL LRGEAIKYLT EALQSISELE LEDKLEKIIN
60 70 80 90 100
AVEKQPLSSN MIERSVVEAA VQECSQSVDE TIEHVFNIIG AFDIPRFVYN
110 120 130 140 150
SERKKFLPLL MTNHPAPNLF GTPRDKAEMF RERYTILHQR THRHELFTPP
160 170 180 190 200
VIGSHPDESG SKFQLKTIET LLGSTTKIGD AIVLGMITQL KEGKFFLEDP
210 220 230 240 250
TGTVQLDLSK AQFHSGLYTE ACFVLAEGWF EDQVFHVNAF GFPPTEPSST
260 270 280 290 300
TRAYYGNINF FGGPSNTSVK TSAKLKQLEE ENKDAMFVFL SDVWLDQVEV
310 320 330 340 350
LEKLRIMFAG YSPAPPTCFI LCGNFSSAPY GKNQVQALKD SLKTLADIIC
360 370 380 390 400
EYPDIHQSSR FVFVPGPEDP GFGSILPRPP LAESITNEFR QRVPFSVFTT
410 420 430 440 450
NPCRIQYCTQ EITVFREDLV NKMCRNCVRF PSSNLAIPNH FVKTILSQGH
460 470 480 490 500
LTPLPLYVCP VYWAYDYALR VYPVPDLLVI ADKYDPFTTT NTECLCINPG
510 520
SFPRSGFSFK VFYPSNKTVE DSKLQGF
Length:527
Mass (Da):59,537
Last modified:December 15, 1998 - v2
Checksum:iAFA7AF7C2C0BFF15
GO
Isoform 2 (identifier: P56282-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     83-108: Missing.

Note: No experimental confirmation available.

Show »
Length:501
Mass (Da):56,418
Checksum:iECB4BFD1E2FDAE1C
GO
Isoform 3 (identifier: P56282-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     500-527: GSFPRSGFSFKVFYPSNKTVEDSKLQGF → VRM

Show »
Length:502
Mass (Da):56,784
Checksum:i0F3391E93AB14483
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti11 – 111L → P in AAC51920 (PubMed:9405441).Curated
Sequence conflicti359 – 3591Missing in AAC51920 (PubMed:9405441).Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti84 – 841H → P.1 Publication
Corresponds to variant rs34857719 [ dbSNP | Ensembl ].
VAR_044379
Natural varianti456 – 4561L → V.
Corresponds to variant rs34574266 [ dbSNP | Ensembl ].
VAR_044380
Natural varianti514 – 5141P → L.1 Publication
Corresponds to variant rs45515094 [ dbSNP | Ensembl ].
VAR_044381

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei83 – 10826Missing in isoform 2. 1 PublicationVSP_042551Add
BLAST
Alternative sequencei500 – 52728GSFPR…KLQGF → VRM in isoform 3. 1 PublicationVSP_043796Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF025840 mRNA. Translation: AAC51920.1.
AF036899 mRNA. Translation: AAC39610.1.
AF387034
, AF387021, AF387022, AF387023, AF387024, AF387025, AF387026, AF387027, AF387028, AF387029, AF387030, AF387031, AF387032, AF387033 Genomic DNA. Translation: AAK72254.1.
EF506887 Genomic DNA. Translation: ABO43040.1.
AK293163 mRNA. Translation: BAG56707.1.
AL139099 Genomic DNA. No translation available.
AL591767 Genomic DNA. No translation available.
BC112962 mRNA. Translation: AAI12963.1.
BC126218 mRNA. Translation: AAI26219.1.
BC126220 mRNA. Translation: AAI26221.1.
CCDSiCCDS32073.1. [P56282-1]
CCDS55914.1. [P56282-2]
CCDS55915.1. [P56282-3]
RefSeqiNP_001184259.1. NM_001197330.1. [P56282-2]
NP_001184260.1. NM_001197331.1. [P56282-3]
NP_002683.2. NM_002692.3. [P56282-1]
UniGeneiHs.162777.

Genome annotation databases

EnsembliENST00000216367; ENSP00000216367; ENSG00000100479. [P56282-1]
ENST00000539565; ENSP00000446313; ENSG00000100479. [P56282-2]
ENST00000554396; ENSP00000451621; ENSG00000100479. [P56282-3]
GeneIDi5427.
KEGGihsa:5427.
UCSCiuc001wwu.3. human. [P56282-1]
uc010ano.3. human. [P56282-3]
uc021rsr.1. human. [P56282-2]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Web resourcesi

NIEHS-SNPs

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF025840 mRNA. Translation: AAC51920.1.
AF036899 mRNA. Translation: AAC39610.1.
AF387034
, AF387021, AF387022, AF387023, AF387024, AF387025, AF387026, AF387027, AF387028, AF387029, AF387030, AF387031, AF387032, AF387033 Genomic DNA. Translation: AAK72254.1.
EF506887 Genomic DNA. Translation: ABO43040.1.
AK293163 mRNA. Translation: BAG56707.1.
AL139099 Genomic DNA. No translation available.
AL591767 Genomic DNA. No translation available.
BC112962 mRNA. Translation: AAI12963.1.
BC126218 mRNA. Translation: AAI26219.1.
BC126220 mRNA. Translation: AAI26221.1.
CCDSiCCDS32073.1. [P56282-1]
CCDS55914.1. [P56282-2]
CCDS55915.1. [P56282-3]
RefSeqiNP_001184259.1. NM_001197330.1. [P56282-2]
NP_001184260.1. NM_001197331.1. [P56282-3]
NP_002683.2. NM_002692.3. [P56282-1]
UniGeneiHs.162777.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2V6ZNMR-M1-73[»]
ProteinModelPortaliP56282.
SMRiP56282. Positions 1-75.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi111423. 26 interactions.
IntActiP56282. 13 interactions.
MINTiMINT-1377461.
STRINGi9606.ENSP00000216367.

Chemistry

DrugBankiDB00242. Cladribine.

PTM databases

PhosphoSiteiP56282.

Polymorphism and mutation databases

BioMutaiPOLE2.
DMDMi3915676.

Proteomic databases

MaxQBiP56282.
PaxDbiP56282.
PRIDEiP56282.

Protocols and materials databases

DNASUi5427.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000216367; ENSP00000216367; ENSG00000100479. [P56282-1]
ENST00000539565; ENSP00000446313; ENSG00000100479. [P56282-2]
ENST00000554396; ENSP00000451621; ENSG00000100479. [P56282-3]
GeneIDi5427.
KEGGihsa:5427.
UCSCiuc001wwu.3. human. [P56282-1]
uc010ano.3. human. [P56282-3]
uc021rsr.1. human. [P56282-2]

Organism-specific databases

CTDi5427.
GeneCardsiGC14M050110.
HGNCiHGNC:9178. POLE2.
HPAiHPA027555.
MIMi602670. gene.
neXtProtiNX_P56282.
PharmGKBiPA278.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG311342.
GeneTreeiENSGT00390000012435.
HOGENOMiHOG000265254.
HOVERGENiHBG061290.
InParanoidiP56282.
KOiK02325.
OMAiILQQRTH.
OrthoDBiEOG725DH7.
PhylomeDBiP56282.
TreeFamiTF103007.

Enzyme and pathway databases

ReactomeiREACT_1095. Activation of the pre-replicative complex.
REACT_1993. Repair synthesis for gap-filling by DNA polymerase in TC-NER.
REACT_2244. DNA replication initiation.
REACT_355250. Termination of translesion DNA synthesis.
REACT_355480. Recognition of DNA damage by PCNA-containing replication complex.
REACT_355510. PCNA-Dependent Long Patch Base Excision Repair.
REACT_378. Repair synthesis of patch ~27-30 bases long by DNA polymerase.
REACT_7993. Telomere C-strand synthesis initiation.

Miscellaneous databases

EvolutionaryTraceiP56282.
GeneWikiiPOLE2.
GenomeRNAii5427.
NextBioi20997.
PROiP56282.
SOURCEiSearch...

Gene expression databases

BgeeiP56282.
CleanExiHS_POLE2.
ExpressionAtlasiP56282. baseline and differential.
GenevestigatoriP56282.

Family and domain databases

InterProiIPR007185. DNA_pol_alpha/epsilon_bsu.
IPR016266. DNA_pol_e_bsu.
IPR024639. DNA_pol_e_bsu_N.
[Graphical view]
PfamiPF04042. DNA_pol_E_B. 1 hit.
PF12213. Dpoe2NT. 1 hit.
[Graphical view]
PIRSFiPIRSF000799. DNA_pol_eps_2. 1 hit.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Purification, cDNA cloning, and gene mapping of the small subunit of human DNA polymerase epsilon."
    Li Y., Asahara H., Patel V.S., Zhou S., Linn S.
    J. Biol. Chem. 272:32337-32344(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  2. "The small subunits of human and mouse DNA polymerase epsilon are homologous to the second largest subunit of the yeast Saccharomyces cerevisiae DNA polymerase epsilon."
    Jokela M., Makiniemi M., Lehtonen S., Szpirer C., Hellman U., Syvaeoja J.E.
    Nucleic Acids Res. 26:730-734(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  3. "E2F mediates induction of the Sp1-controlled promoter of the human DNA polymerase varepsilon B-subunit gene POLE2."
    Huang D., Jokela M., Tuusa J., Skog S., Poikonen K., Syvaoja J.E.
    Nucleic Acids Res. 29:2810-2821(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
  4. NIEHS SNPs program
    Submitted (MAR-2007) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], VARIANTS PRO-84 AND LEU-514.
  5. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
  6. "The DNA sequence and analysis of human chromosome 14."
    Heilig R., Eckenberg R., Petit J.-L., Fonknechten N., Da Silva C., Cattolico L., Levy M., Barbe V., De Berardinis V., Ureta-Vidal A., Pelletier E., Vico V., Anthouard V., Rowen L., Madan A., Qin S., Sun H., Du H.
    , Pepin K., Artiguenave F., Robert C., Cruaud C., Bruels T., Jaillon O., Friedlander L., Samson G., Brottier P., Cure S., Segurens B., Aniere F., Samain S., Crespeau H., Abbasi N., Aiach N., Boscus D., Dickhoff R., Dors M., Dubois I., Friedman C., Gouyvenoux M., James R., Madan A., Mairey-Estrada B., Mangenot S., Martins N., Menard M., Oztas S., Ratcliffe A., Shaffer T., Trask B., Vacherie B., Bellemere C., Belser C., Besnard-Gonnet M., Bartol-Mavel D., Boutard M., Briez-Silla S., Combette S., Dufosse-Laurent V., Ferron C., Lechaplais C., Louesse C., Muselet D., Magdelenat G., Pateau E., Petit E., Sirvain-Trukniewicz P., Trybou A., Vega-Czarny N., Bataille E., Bluet E., Bordelais I., Dubois M., Dumont C., Guerin T., Haffray S., Hammadi R., Muanga J., Pellouin V., Robert D., Wunderle E., Gauguet G., Roy A., Sainte-Marthe L., Verdier J., Verdier-Discala C., Hillier L.W., Fulton L., McPherson J., Matsuda F., Wilson R., Scarpelli C., Gyapay G., Wincker P., Saurin W., Quetier F., Waterston R., Hood L., Weissenbach J.
    Nature 421:601-607(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  7. "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(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 3).
    Tissue: Embryonic stem cell.
  8. "Identification and cloning of two histone fold motif-containing subunits of HeLa DNA polymerase epsilon."
    Li Y., Pursell Z.F., Linn S.
    J. Biol. Chem. 275:23247-23252(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION IN EPSILON DNA POLYMERASE COMPLEX.
    Tissue: Cervix carcinoma.

Entry informationi

Entry nameiDPOE2_HUMAN
AccessioniPrimary (citable) accession number: P56282
Secondary accession number(s): A0AV55
, A4FU92, A4LBB7, A6NH58, B4DDE6, O43560
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 15, 1998
Last sequence update: December 15, 1998
Last modified: May 27, 2015
This is version 128 of the entry and version 2 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

Miscellaneous

In eukaryotes there are five DNA polymerases: alpha, beta, gamma, delta, and epsilon which are responsible for different reactions of DNA synthesis.

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 14
    Human chromosome 14: 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.