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Protein

Glutathione S-transferase P

Gene

GSTP1

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

Functioni

Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. Regulates negatively CDK5 activity via p25/p35 translocation to prevent neurodegeneration.1 Publication

Catalytic activityi

RX + glutathione = HX + R-S-glutathione.3 Publications

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei8 – 81Glutathione7 Publications
Binding sitei14 – 141Glutathione7 Publications
Binding sitei39 – 391Glutathione7 Publications
Binding sitei45 – 451Glutathione7 Publications

GO - Molecular functioni

  • dinitrosyl-iron complex binding Source: BHF-UCL
  • drug binding Source: Ensembl
  • glutathione binding Source: Ensembl
  • glutathione transferase activity Source: UniProtKB
  • JUN kinase binding Source: BHF-UCL
  • kinase regulator activity Source: BHF-UCL
  • nitric oxide binding Source: BHF-UCL
  • S-nitrosoglutathione binding Source: BHF-UCL

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Transferase

Enzyme and pathway databases

BRENDAi2.5.1.18. 2681.
ReactomeiR-HSA-156590. Glutathione conjugation.
R-HSA-3299685. Detoxification of Reactive Oxygen Species.
SABIO-RKP09211.
SIGNORiP09211.

Chemistry

SwissLipidsiSLP:000001615.

Names & Taxonomyi

Protein namesi
Recommended name:
Glutathione S-transferase P (EC:2.5.1.18)
Alternative name(s):
GST class-pi
GSTP1-1
Gene namesi
Name:GSTP1
Synonyms:FAEES3, GST3
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 11

Organism-specific databases

HGNCiHGNC:4638. GSTP1.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: UniProtKB
  • cytosol Source: Reactome
  • extracellular exosome Source: UniProtKB
  • extracellular space Source: UniProtKB
  • intracellular Source: BHF-UCL
  • mitochondrion Source: HPA
  • nucleus Source: UniProtKB-SubCell
  • plasma membrane Source: Ensembl
  • TRAF2-GSTP1 complex Source: BHF-UCL
  • vesicle Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Mitochondrion, Nucleus

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi8 – 81Y → F: Reduces catalytic activity about 50-fold. 2 Publications
Mutagenesisi99 – 991D → A: Reduces affinity for glutathione. Slightly reduced catalytic activity. 1 Publication

Organism-specific databases

PharmGKBiPA29028.

Chemistry

ChEMBLiCHEMBL3902.
DrugBankiDB01008. Busulfan.
DB04339. Carbocisteine.
DB00958. Carboplatin.
DB00291. Chlorambucil.
DB00515. Cisplatin.
DB01242. Clomipramine.
DB00773. Etoposide.
DB00143. Glutathione.
DB00526. Oxaliplatin.
DB00163. Vitamin E.

Polymorphism and mutation databases

BioMutaiGSTP1.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methionineiRemovedCombined sources5 Publications
Chaini2 – 210209Glutathione S-transferase PPRO_0000185900Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei4 – 41Phosphotyrosine; by EGFR1 Publication
Modified residuei62 – 621PhosphothreonineCombined sources
Modified residuei103 – 1031N6-succinyllysineBy similarity
Modified residuei116 – 1161N6-succinyllysineBy similarity
Modified residuei128 – 1281N6-acetyllysineCombined sources
Modified residuei199 – 1991Phosphotyrosine; by EGFR1 Publication

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

EPDiP09211.
PaxDbiP09211.
PeptideAtlasiP09211.
PRIDEiP09211.
TopDownProteomicsiP09211.

2D gel databases

DOSAC-COBS-2DPAGEP09211.
OGPiP09211.
REPRODUCTION-2DPAGEIPI00219757.
SWISS-2DPAGEP09211.
UCD-2DPAGEP09211.

PTM databases

iPTMnetiP09211.
PhosphoSiteiP09211.
SwissPalmiP09211.

Miscellaneous databases

PMAP-CutDBP09211.

Expressioni

Gene expression databases

BgeeiENSG00000084207.
CleanExiHS_GSTP1.
ExpressionAtlasiP09211. baseline and differential.
GenevisibleiP09211. HS.

Organism-specific databases

HPAiHPA019779.
HPA019869.

Interactioni

Subunit structurei

Homodimer. Interacts with CDK5.2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
APPBP2Q926243EBI-353467,EBI-743771
KRT31Q153233EBI-353467,EBI-948001
KRTAP10-7P604093EBI-353467,EBI-10172290
KRTAP10-9P604113EBI-353467,EBI-10172052
NOTCH2NLQ7Z3S93EBI-353467,EBI-945833
PRDX6P300412EBI-353467,EBI-2255129
TRAF2Q129335EBI-353467,EBI-355744

GO - Molecular functioni

Protein-protein interaction databases

BioGridi109205. 44 interactions.
IntActiP09211. 40 interactions.
MINTiMINT-4998983.
STRINGi9606.ENSP00000381607.

Chemistry

BindingDBiP09211.

Structurei

Secondary structure

1
210
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi3 – 86Combined sources
Beta strandi10 – 123Combined sources
Helixi13 – 153Combined sources
Helixi16 – 249Combined sources
Beta strandi29 – 335Combined sources
Helixi36 – 416Combined sources
Helixi43 – 475Combined sources
Beta strandi48 – 514Combined sources
Beta strandi55 – 584Combined sources
Beta strandi61 – 644Combined sources
Helixi66 – 7611Combined sources
Helixi84 – 11027Combined sources
Helixi112 – 13524Combined sources
Helixi138 – 1403Combined sources
Beta strandi144 – 1485Combined sources
Helixi151 – 16616Combined sources
Helixi170 – 1734Combined sources
Helixi175 – 18511Combined sources
Helixi188 – 1958Combined sources
Helixi197 – 2004Combined sources
Beta strandi204 – 2085Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
10GSX-ray2.20A/B2-210[»]
11GSX-ray2.30A/B1-210[»]
12GSX-ray2.10A/B1-210[»]
13GSX-ray1.90A/B1-210[»]
14GSX-ray2.80A/B1-210[»]
16GSX-ray1.90A/B1-210[»]
17GSX-ray1.90A/B1-210[»]
18GSX-ray1.90A/B1-210[»]
19GSX-ray1.90A/B2-210[»]
1AQVX-ray1.94A/B2-210[»]
1AQWX-ray1.80A/B/C/D2-210[»]
1AQXX-ray2.00A/B/C/D2-210[»]
1EOGX-ray2.10A/B3-210[»]
1EOHX-ray2.50A/B/C/D/E/F/G/H2-210[»]
1GSSX-ray2.80A/B2-210[»]
1KBNX-ray2.00A/B2-210[»]
1LBKX-ray1.86A/B2-203[»]
1MD3X-ray2.03A/B2-210[»]
1MD4X-ray2.10A/B2-210[»]
1PGTX-ray1.80A/B1-210[»]
1PX6X-ray2.10A/B2-210[»]
1PX7X-ray2.03A/B2-210[»]
1ZGNX-ray2.10A/B2-210[»]
20GSX-ray2.45A/B2-210[»]
22GSX-ray1.90A/B1-210[»]
2A2RX-ray1.40A/B1-210[»]
2A2SX-ray1.70A/B1-210[»]
2GSSX-ray1.90A/B2-210[»]
2J9HX-ray2.40A/B2-210[»]
2PGTX-ray1.90A/B1-210[»]
3CSHX-ray1.55A/B2-210[»]
3CSIX-ray1.90A/B/C/D2-210[»]
3CSJX-ray1.90A/B2-210[»]
3DD3X-ray2.25A/B1-210[»]
3DGQX-ray1.60A/B1-210[»]
3GSSX-ray1.90A/B2-210[»]
3GUSX-ray1.53A/B2-210[»]
3HJMX-ray2.10A/B/C/D2-210[»]
3HJOX-ray1.95A/B2-210[»]
3HKRX-ray1.80A/B2-210[»]
3IE3X-ray1.80A/B2-210[»]
3KM6X-ray2.10A/B2-210[»]
3KMNX-ray1.80A/B2-210[»]
3KMOX-ray2.60A/B2-210[»]
3N9JX-ray1.85A/B1-210[»]
3PGTX-ray2.14A/B1-210[»]
4GSSX-ray2.50A/B2-210[»]
4PGTX-ray2.10A/B1-210[»]
5GSSX-ray1.95A/B2-210[»]
6GSSX-ray1.90A/B2-210[»]
7GSSX-ray2.20A/B2-210[»]
8GSSX-ray1.90A/B/C2-210[»]
9GSSX-ray1.97A/B2-210[»]
ProteinModelPortaliP09211.
SMRiP09211. Positions 1-210.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP09211.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini2 – 8180GST N-terminalAdd
BLAST
Domaini83 – 204122GST C-terminalAdd
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni52 – 532Glutathione binding7 Publications
Regioni65 – 662Glutathione binding7 Publications

Sequence similaritiesi

Belongs to the GST superfamily. Pi family.Curated
Contains 1 GST C-terminal domain.Curated
Contains 1 GST N-terminal domain.Curated

Phylogenomic databases

eggNOGiKOG1695. Eukaryota.
ENOG4111VAU. LUCA.
GeneTreeiENSGT00550000074559.
HOGENOMiHOG000115733.
HOVERGENiHBG108324.
InParanoidiP09211.
KOiK00799.
OMAiLRCKYAT.
OrthoDBiEOG091G0K2E.
PhylomeDBiP09211.
TreeFamiTF105321.

Family and domain databases

Gene3Di1.20.1050.10. 1 hit.
3.40.30.10. 1 hit.
InterProiIPR010987. Glutathione-S-Trfase_C-like.
IPR004045. Glutathione_S-Trfase_N.
IPR004046. GST_C.
IPR003082. GST_pi.
IPR012336. Thioredoxin-like_fold.
[Graphical view]
PfamiPF14497. GST_C_3. 1 hit.
PF02798. GST_N. 1 hit.
[Graphical view]
PRINTSiPR01268. GSTRNSFRASEP.
SUPFAMiSSF47616. SSF47616. 1 hit.
SSF52833. SSF52833. 1 hit.
PROSITEiPS50405. GST_CTER. 1 hit.
PS50404. GST_NTER. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P09211-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MPPYTVVYFP VRGRCAALRM LLADQGQSWK EEVVTVETWQ EGSLKASCLY
60 70 80 90 100
GQLPKFQDGD LTLYQSNTIL RHLGRTLGLY GKDQQEAALV DMVNDGVEDL
110 120 130 140 150
RCKYISLIYT NYEAGKDDYV KALPGQLKPF ETLLSQNQGG KTFIVGDQIS
160 170 180 190 200
FADYNLLDLL LIHEVLAPGC LDAFPLLSAY VGRLSARPKL KAFLASPEYV
210
NLPINGNGKQ
Length:210
Mass (Da):23,356
Last modified:January 23, 2007 - v2
Checksum:i409E33FFAA338396
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti186 – 1861A → P in CAA30894 (PubMed:3196325).Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti105 – 1051I → V in allele GSTP1*B and allele GSTP1*C. 3 Publications
Corresponds to variant rs1695 [ dbSNP | Ensembl ].
VAR_014499
Natural varianti114 – 1141A → V in allele GSTP1*C. 2 Publications
Corresponds to variant rs1138272 [ dbSNP | Ensembl ].
VAR_014500
Natural varianti169 – 1691G → D.
Corresponds to variant rs41462048 [ dbSNP | Ensembl ].
VAR_049493

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X06547 mRNA. Translation: CAA29794.1.
M24485 Genomic DNA. Translation: AAA56823.1.
X08058 Genomic DNA. Translation: CAA30847.1.
X08094, X08095, X08096 Genomic DNA. Translation: CAA30894.1.
X15480 mRNA. Translation: CAA33508.1.
U12472 Genomic DNA. Translation: AAA64919.1.
U30897 mRNA. Translation: AAC51280.1.
U62589 mRNA. Translation: AAC51237.1.
U21689 Genomic DNA. Translation: AAC13869.1.
BT019949 mRNA. Translation: AAV38752.1.
BT019950 mRNA. Translation: AAV38753.1.
CR450361 mRNA. Translation: CAG29357.1.
AY324387 Genomic DNA. Translation: AAP72967.1.
BC010915 mRNA. Translation: AAH10915.1.
CCDSiCCDS41679.1.
PIRiA41177.
JS0153. A37378.
RefSeqiNP_000843.1. NM_000852.3.
UniGeneiHs.523836.

Genome annotation databases

EnsembliENST00000398606; ENSP00000381607; ENSG00000084207.
GeneIDi2950.
KEGGihsa:2950.

Keywords - Coding sequence diversityi

Polymorphism

Cross-referencesi

Web resourcesi

NIEHS-SNPs
SHMPD

The Singapore human mutation and polymorphism database

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X06547 mRNA. Translation: CAA29794.1.
M24485 Genomic DNA. Translation: AAA56823.1.
X08058 Genomic DNA. Translation: CAA30847.1.
X08094, X08095, X08096 Genomic DNA. Translation: CAA30894.1.
X15480 mRNA. Translation: CAA33508.1.
U12472 Genomic DNA. Translation: AAA64919.1.
U30897 mRNA. Translation: AAC51280.1.
U62589 mRNA. Translation: AAC51237.1.
U21689 Genomic DNA. Translation: AAC13869.1.
BT019949 mRNA. Translation: AAV38752.1.
BT019950 mRNA. Translation: AAV38753.1.
CR450361 mRNA. Translation: CAG29357.1.
AY324387 Genomic DNA. Translation: AAP72967.1.
BC010915 mRNA. Translation: AAH10915.1.
CCDSiCCDS41679.1.
PIRiA41177.
JS0153. A37378.
RefSeqiNP_000843.1. NM_000852.3.
UniGeneiHs.523836.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
10GSX-ray2.20A/B2-210[»]
11GSX-ray2.30A/B1-210[»]
12GSX-ray2.10A/B1-210[»]
13GSX-ray1.90A/B1-210[»]
14GSX-ray2.80A/B1-210[»]
16GSX-ray1.90A/B1-210[»]
17GSX-ray1.90A/B1-210[»]
18GSX-ray1.90A/B1-210[»]
19GSX-ray1.90A/B2-210[»]
1AQVX-ray1.94A/B2-210[»]
1AQWX-ray1.80A/B/C/D2-210[»]
1AQXX-ray2.00A/B/C/D2-210[»]
1EOGX-ray2.10A/B3-210[»]
1EOHX-ray2.50A/B/C/D/E/F/G/H2-210[»]
1GSSX-ray2.80A/B2-210[»]
1KBNX-ray2.00A/B2-210[»]
1LBKX-ray1.86A/B2-203[»]
1MD3X-ray2.03A/B2-210[»]
1MD4X-ray2.10A/B2-210[»]
1PGTX-ray1.80A/B1-210[»]
1PX6X-ray2.10A/B2-210[»]
1PX7X-ray2.03A/B2-210[»]
1ZGNX-ray2.10A/B2-210[»]
20GSX-ray2.45A/B2-210[»]
22GSX-ray1.90A/B1-210[»]
2A2RX-ray1.40A/B1-210[»]
2A2SX-ray1.70A/B1-210[»]
2GSSX-ray1.90A/B2-210[»]
2J9HX-ray2.40A/B2-210[»]
2PGTX-ray1.90A/B1-210[»]
3CSHX-ray1.55A/B2-210[»]
3CSIX-ray1.90A/B/C/D2-210[»]
3CSJX-ray1.90A/B2-210[»]
3DD3X-ray2.25A/B1-210[»]
3DGQX-ray1.60A/B1-210[»]
3GSSX-ray1.90A/B2-210[»]
3GUSX-ray1.53A/B2-210[»]
3HJMX-ray2.10A/B/C/D2-210[»]
3HJOX-ray1.95A/B2-210[»]
3HKRX-ray1.80A/B2-210[»]
3IE3X-ray1.80A/B2-210[»]
3KM6X-ray2.10A/B2-210[»]
3KMNX-ray1.80A/B2-210[»]
3KMOX-ray2.60A/B2-210[»]
3N9JX-ray1.85A/B1-210[»]
3PGTX-ray2.14A/B1-210[»]
4GSSX-ray2.50A/B2-210[»]
4PGTX-ray2.10A/B1-210[»]
5GSSX-ray1.95A/B2-210[»]
6GSSX-ray1.90A/B2-210[»]
7GSSX-ray2.20A/B2-210[»]
8GSSX-ray1.90A/B/C2-210[»]
9GSSX-ray1.97A/B2-210[»]
ProteinModelPortaliP09211.
SMRiP09211. Positions 1-210.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi109205. 44 interactions.
IntActiP09211. 40 interactions.
MINTiMINT-4998983.
STRINGi9606.ENSP00000381607.

Chemistry

BindingDBiP09211.
ChEMBLiCHEMBL3902.
DrugBankiDB01008. Busulfan.
DB04339. Carbocisteine.
DB00958. Carboplatin.
DB00291. Chlorambucil.
DB00515. Cisplatin.
DB01242. Clomipramine.
DB00773. Etoposide.
DB00143. Glutathione.
DB00526. Oxaliplatin.
DB00163. Vitamin E.
SwissLipidsiSLP:000001615.

PTM databases

iPTMnetiP09211.
PhosphoSiteiP09211.
SwissPalmiP09211.

Polymorphism and mutation databases

BioMutaiGSTP1.

2D gel databases

DOSAC-COBS-2DPAGEP09211.
OGPiP09211.
REPRODUCTION-2DPAGEIPI00219757.
SWISS-2DPAGEP09211.
UCD-2DPAGEP09211.

Proteomic databases

EPDiP09211.
PaxDbiP09211.
PeptideAtlasiP09211.
PRIDEiP09211.
TopDownProteomicsiP09211.

Protocols and materials databases

DNASUi2950.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000398606; ENSP00000381607; ENSG00000084207.
GeneIDi2950.
KEGGihsa:2950.

Organism-specific databases

CTDi2950.
GeneCardsiGSTP1.
HGNCiHGNC:4638. GSTP1.
HPAiHPA019779.
HPA019869.
MIMi134660. gene.
neXtProtiNX_P09211.
PharmGKBiPA29028.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG1695. Eukaryota.
ENOG4111VAU. LUCA.
GeneTreeiENSGT00550000074559.
HOGENOMiHOG000115733.
HOVERGENiHBG108324.
InParanoidiP09211.
KOiK00799.
OMAiLRCKYAT.
OrthoDBiEOG091G0K2E.
PhylomeDBiP09211.
TreeFamiTF105321.

Enzyme and pathway databases

BRENDAi2.5.1.18. 2681.
ReactomeiR-HSA-156590. Glutathione conjugation.
R-HSA-3299685. Detoxification of Reactive Oxygen Species.
SABIO-RKP09211.
SIGNORiP09211.

Miscellaneous databases

ChiTaRSiGSTP1. human.
EvolutionaryTraceiP09211.
GeneWikiiGSTP1.
GenomeRNAii2950.
PMAP-CutDBP09211.
PROiP09211.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000084207.
CleanExiHS_GSTP1.
ExpressionAtlasiP09211. baseline and differential.
GenevisibleiP09211. HS.

Family and domain databases

Gene3Di1.20.1050.10. 1 hit.
3.40.30.10. 1 hit.
InterProiIPR010987. Glutathione-S-Trfase_C-like.
IPR004045. Glutathione_S-Trfase_N.
IPR004046. GST_C.
IPR003082. GST_pi.
IPR012336. Thioredoxin-like_fold.
[Graphical view]
PfamiPF14497. GST_C_3. 1 hit.
PF02798. GST_N. 1 hit.
[Graphical view]
PRINTSiPR01268. GSTRNSFRASEP.
SUPFAMiSSF47616. SSF47616. 1 hit.
SSF52833. SSF52833. 1 hit.
PROSITEiPS50405. GST_CTER. 1 hit.
PS50404. GST_NTER. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiGSTP1_HUMAN
AccessioniPrimary (citable) accession number: P09211
Secondary accession number(s): O00460, Q15690, Q5TZY3
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 1, 1989
Last sequence update: January 23, 2007
Last modified: September 7, 2016
This is version 199 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

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 11
    Human chromosome 11: 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

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 one 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.