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Protein

PHD finger protein 20

Gene

PHF20

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

Functioni

Methyllysine-binding protein, component of the MOF histone acetyltransferase protein complex. Not required for maintaining the global histone H4 'Lys-16' acetylation (H4K16ac) levels or locus specific histone acetylation, but instead works downstream in transcriptional regulation of MOF target genes (By similarity). As part of the NSL complex it may be involved in acetylation of nucleosomal histone H4 on several lysine residues. Contributes to methyllysine-dependent p53/TP53 stabilization and up-regulation after DNA damage.By similarity2 Publications

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
DNA bindingi257 – 269A.T hookAdd BLAST13
Zinc fingeri452 – 477C2H2-typePROSITE-ProRule annotationAdd BLAST26
Zinc fingeri654 – 700PHD-typeAdd BLAST47

GO - Molecular functioni

GO - Biological processi

  • histone H4-K16 acetylation Source: UniProtKB
  • histone H4-K5 acetylation Source: UniProtKB
  • histone H4-K8 acetylation Source: UniProtKB
  • regulation of signal transduction by p53 class mediator Source: Reactome
  • regulation of transcription, DNA-templated Source: UniProtKB-KW
  • transcription, DNA-templated Source: UniProtKB-KW
Complete GO annotation...

Keywords - Molecular functioni

Chromatin regulator

Keywords - Biological processi

Transcription, Transcription regulation

Keywords - Ligandi

DNA-binding, Metal-binding, Zinc

Enzyme and pathway databases

ReactomeiR-HSA-3214847. HATs acetylate histones.
R-HSA-6804759. Regulation of TP53 Activity through Association with Co-factors.
SIGNORiQ9BVI0.

Names & Taxonomyi

Protein namesi
Recommended name:
PHD finger protein 20
Alternative name(s):
Glioma-expressed antigen 2
Hepatocellular carcinoma-associated antigen 58
Novel zinc finger protein
Transcription factor TZP
Gene namesi
Name:PHF20
Synonyms:C20orf104, GLEA2, HCA58, NZF, TZP
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 20

Organism-specific databases

HGNCiHGNC:16098. PHF20.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: HPA
  • cytosol Source: Reactome
  • histone acetyltransferase complex Source: UniProtKB
  • MLL1 complex Source: UniProtKB
  • nuclear membrane Source: HPA
  • nucleoplasm Source: HPA
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi96C → S: Abolishes homodimerization. 1 Publication1
Mutagenesisi97W → A: Abolishes interaction with methylated p53. 1 Publication1
Mutagenesisi100C → S: Abolishes homodimerization. 1 Publication1
Mutagenesisi103Y → A: Abolishes interaction with methylated p53. 1 Publication1

Organism-specific databases

DisGeNETi51230.
OpenTargetsiENSG00000025293.
PharmGKBiPA25644.

Polymorphism and mutation databases

BioMutaiPHF20.
DMDMi32699605.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00000593101 – 1012PHD finger protein 20Add BLAST1012

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Disulfide bondi96Interchain (with C-100)1 Publication
Disulfide bondi100Interchain (with C-96)1 Publication
Modified residuei159PhosphoserineCombined sources1
Modified residuei488PhosphoserineCombined sources1
Modified residuei843N6-acetyllysineCombined sources1
Modified residuei878PhosphoserineCombined sources1
Modified residuei880PhosphoserineCombined sources1

Keywords - PTMi

Acetylation, Disulfide bond, Phosphoprotein

Proteomic databases

EPDiQ9BVI0.
MaxQBiQ9BVI0.
PaxDbiQ9BVI0.
PeptideAtlasiQ9BVI0.
PRIDEiQ9BVI0.

PTM databases

iPTMnetiQ9BVI0.
PhosphoSitePlusiQ9BVI0.

Expressioni

Tissue specificityi

Expressed in heart, kidney, liver, lung, pancreas, placenta, spleen and testis. Not expressed in brain, skeletal muscle, colon, ovary, prostate, small intestine and thymus. Expressed in colon and ovary cancer cell lines while it is not expressed in the respective normal tissues.1 Publication

Gene expression databases

BgeeiENSG00000025293.
CleanExiHS_PHF20.
ExpressionAtlasiQ9BVI0. baseline and differential.
GenevisibleiQ9BVI0. HS.

Organism-specific databases

HPAiHPA029619.
HPA029620.
HPA029621.

Interactioni

Subunit structurei

Homodimer; disulfide-linked. Component of some MLL1/MLL complex, at least composed of the core components KMT2A/MLL1, ASH2L, HCFC1, WDR5 and RBBP5, as well as the facultative components BAP18, CHD8, E2F6, HSP70, INO80C, KANSL1, LAS1L, MAX, MCRS1, MGA, KAT8/MOF, PELP1, PHF20, PRP31, RING2, RUVB1/TIP49A, RUVB2/TIP49B, SENP3, TAF1, TAF4, TAF6, TAF7, TAF9 and TEX10. Component of the NSL complex at least composed of MOF/KAT8, KANSL1, KANSL2, KANSL3, MCRS1, PHF20, OGT1/OGT, WDR5 and HCFC1.3 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
HIST1H3DP684316EBI-2560802,EBI-79722
HIST2H4BP628053EBI-2560802,EBI-302023

Protein-protein interaction databases

BioGridi119393. 18 interactors.
IntActiQ9BVI0. 9 interactors.
MINTiMINT-2829252.
STRINGi9606.ENSP00000363124.

Structurei

Secondary structure

11012
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi18 – 22Combined sources5
Beta strandi28 – 37Combined sources10
Turni38 – 41Combined sources4
Beta strandi42 – 47Combined sources6
Helixi52 – 54Combined sources3
Beta strandi56 – 59Combined sources4
Beta strandi92 – 96Combined sources5
Beta strandi102 – 110Combined sources9
Beta strandi114 – 120Combined sources7
Beta strandi125 – 129Combined sources5
Helixi130 – 132Combined sources3
Beta strandi133 – 135Combined sources3

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2LDMNMR-A84-147[»]
3P8DX-ray2.00A/B84-147[»]
3Q1JX-ray2.35A4-69[»]
3QIIX-ray2.30A83-150[»]
3SD4X-ray1.93A/B4-69[»]
5TBNNMR-A646-699[»]
ProteinModelPortaliQ9BVI0.
SMRiQ9BVI0.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ9BVI0.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini4 – 69Tudor 1Add BLAST66
Domaini83 – 147Tudor 2Add BLAST65

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi162 – 221Lys-richAdd BLAST60
Compositional biasi523 – 552Lys-richAdd BLAST30

Domaini

The Tudor domain 2 mediates reading of dimethyl-lysine residues.
The Tudor domain 1 doesn't bind dimethyl-lysine residues, due to an atypical and occluded aromatic cage.

Sequence similaritiesi

Contains 1 A.T hook DNA-binding domain.Curated
Contains 1 C2H2-type zinc finger.PROSITE-ProRule annotation
Contains 1 PHD-type zinc finger.Curated
Contains 2 Tudor domains.Curated

Zinc finger

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri452 – 477C2H2-typePROSITE-ProRule annotationAdd BLAST26
Zinc fingeri654 – 700PHD-typeAdd BLAST47

Keywords - Domaini

Repeat, Zinc-finger

Phylogenomic databases

eggNOGiENOG410IMXB. Eukaryota.
ENOG410XX7Z. LUCA.
GeneTreeiENSGT00390000006451.
HOVERGENiHBG053586.
InParanoidiQ9BVI0.
KOiK18402.
OMAiCYQKPRT.
OrthoDBiEOG091G01T4.
PhylomeDBiQ9BVI0.
TreeFamiTF106475.

Family and domain databases

Gene3Di3.30.40.10. 1 hit.
InterProiIPR022255. DUF3776.
IPR002999. Tudor.
IPR019786. Zinc_finger_PHD-type_CS.
IPR007087. Znf_C2H2.
IPR011011. Znf_FYVE_PHD.
IPR001965. Znf_PHD.
IPR013083. Znf_RING/FYVE/PHD.
[Graphical view]
PfamiPF12618. DUF3776. 1 hit.
[Graphical view]
SMARTiSM00249. PHD. 1 hit.
SM00333. TUDOR. 2 hits.
[Graphical view]
SUPFAMiSSF57903. SSF57903. 1 hit.
PROSITEiPS01359. ZF_PHD_1. 1 hit.
PS00028. ZINC_FINGER_C2H2_1. 1 hit.
PS50157. ZINC_FINGER_C2H2_2. 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: Q9BVI0-1) [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
MTKHPPNRRG ISFEVGAQLE ARDRLKNWYP AHIEDIDYEE GKVLIHFKRW
60 70 80 90 100
NHRYDEWFCW DSPYLRPLEK IQLRKEGLHE EDGSSEFQIN EQVLACWSDC
110 120 130 140 150
RFYPAKVTAV NKDGTYTVKF YDGVVQTVKH IHVKAFSKDQ NIVGNARPKE
160 170 180 190 200
TDHKSLSSSP DKREKFKEQR KATVNVKKDK EDKPLKTEKR PKQPDKEGKL
210 220 230 240 250
ICSEKGKVSE KSLPKNEKED KENISENDRE YSGDAQVDKK PENDIVKSPQ
260 270 280 290 300
ENLREPKRKR GRPPSIAPTA VDSNSQTLQP ITLELRRRKI SKGCEVPLKR
310 320 330 340 350
PRLDKNSSQE KSKNYSENTD KDLSRRRSSR LSTNGTHEIL DPDLVVSDLV
360 370 380 390 400
DTDPLQDTLS STKESEEGQL KSALEAGQVS SALTCHSFGD GSGAAGLELN
410 420 430 440 450
CPSMGENTMK TEPTSPLVEL QEISTVEVTN TFKKTDDFGS SNAPAVDLDH
460 470 480 490 500
KFRCKVVDCL KFFRKAKLLH YHMKYFHGME KSLEPEESPG KRHVQTRGPS
510 520 530 540 550
ASDKPSQETL TRKRVSASSP TTKDKEKNKE KKFKEFVRVK PKKKKKKKKK
560 570 580 590 600
TKPECPCSEE ISDTSQEPSP PKAFAVTRCG SSHKPGVHMS PQLHGPESGH
610 620 630 640 650
HKGKVKALEE DNLSESSSES FLWSDDEYGQ DVDVTTNPDE ELDGDDRYDF
660 670 680 690 700
EVVRCICEVQ EENDFMIQCE ECQCWQHGVC MGLLEENVPE KYTCYVCQDP
710 720 730 740 750
PGQRPGFKYW YDKEWLSRGH MHGLAFLEEN YSHQNAKKIV ATHQLLGDVQ
760 770 780 790 800
RVIEVLHGLQ LKMSILQSRE HPDLPLWCQP WKQHSGEGRS HFRNIPVTDT
810 820 830 840 850
RSKEEAPSYR TLNGAVEKPR PLALPLPRSV EESYITSEHC YQKPRAYYPA
860 870 880 890 900
VEQKLVVETR GSALDDAVNP LHENGDDSLS PRLGWPLDQD RSKGDSDPKP
910 920 930 940 950
GSPKVKEYVS KKALPEEAPA RKLLDRGGEG LLSSQHQWQF NLLTHVESLQ
960 970 980 990 1000
DEVTHRMDSI EKELDVLESW LDYTGELEPP EPLARLPQLK HCIKQLLMDL
1010
GKVQQIALCC ST
Length:1,012
Mass (Da):115,386
Last modified:July 11, 2003 - v2
Checksum:i1CDBADC23D007503
GO
Isoform 2 (identifier: Q9BVI0-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     237-273: VDKKPENDIVKSPQENLREPKRKRGRPPSIAPTAVDS → KTRQTPFHSSYCCGFKLSNFATNNIGTEKKENIKRM
     274-1012: Missing.

Show »
Length:272
Mass (Da):31,856
Checksum:i11C579B3C0050A12
GO

Sequence cautioni

The sequence AAF34184 differs from that shown. Reason: Frameshift at position 260.Curated
The sequence AAK19748 differs from that shown. Reason: Frameshift at positions 635, 653 and 655.Curated

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti221 – 222KE → QG in AAG49888 (PubMed:11703362).Curated2
Sequence conflicti226E → G in AAG49888 (PubMed:11703362).Curated1
Sequence conflicti372S → F in AAH80598 (PubMed:15489334).Curated1
Sequence conflicti516S → F in AAG49888 (PubMed:11703362).Curated1
Sequence conflicti532K → E in BAG37103 (PubMed:14702039).Curated1
Sequence conflicti671E → G in BAG37103 (PubMed:14702039).Curated1
Isoform 2 (identifier: Q9BVI0-2)
Sequence conflicti237 – 239KTR → KKTS in AAF34184 (PubMed:12097419).Curated3

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_051600605V → M.1 PublicationCorresponds to variant rs17431878dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_007760237 – 273VDKKP…TAVDS → KTRQTPFHSSYCCGFKLSNF ATNNIGTEKKENIKRM in isoform 2. 1 PublicationAdd BLAST37
Alternative sequenceiVSP_007761274 – 1012Missing in isoform 2. 1 PublicationAdd BLAST739

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF220416 mRNA. Translation: AAF34184.1. Frameshift.
AF348207 mRNA. Translation: AAK19748.1. Frameshift.
AY027523 mRNA. Translation: AAK13046.1.
AK314503 mRNA. Translation: BAG37103.1.
AL109965, AL078461 Genomic DNA. Translation: CAI19247.1.
AL078461, AL109965 Genomic DNA. Translation: CAI43145.1.
CH471077 Genomic DNA. Translation: EAW76153.1.
CH471077 Genomic DNA. Translation: EAW76155.1.
CH471077 Genomic DNA. Translation: EAW76156.1.
CH471077 Genomic DNA. Translation: EAW76157.1.
BC048210 mRNA. Translation: AAH48210.1.
BC080598 mRNA. Translation: AAH80598.1.
BC093405 mRNA. Translation: AAH93405.1.
BC150178 mRNA. Translation: AAI50179.1.
AF258787 mRNA. Translation: AAG49888.1.
CCDSiCCDS13268.1. [Q9BVI0-1]
RefSeqiNP_057520.2. NM_016436.4. [Q9BVI0-1]
XP_016883353.1. XM_017027864.1. [Q9BVI0-1]
XP_016883354.1. XM_017027865.1. [Q9BVI0-1]
XP_016883355.1. XM_017027866.1. [Q9BVI0-1]
XP_016883356.1. XM_017027867.1. [Q9BVI0-1]
UniGeneiHs.517044.

Genome annotation databases

EnsembliENST00000374012; ENSP00000363124; ENSG00000025293. [Q9BVI0-1]
GeneIDi51230.
KEGGihsa:51230.
UCSCiuc002xek.2. human. [Q9BVI0-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF220416 mRNA. Translation: AAF34184.1. Frameshift.
AF348207 mRNA. Translation: AAK19748.1. Frameshift.
AY027523 mRNA. Translation: AAK13046.1.
AK314503 mRNA. Translation: BAG37103.1.
AL109965, AL078461 Genomic DNA. Translation: CAI19247.1.
AL078461, AL109965 Genomic DNA. Translation: CAI43145.1.
CH471077 Genomic DNA. Translation: EAW76153.1.
CH471077 Genomic DNA. Translation: EAW76155.1.
CH471077 Genomic DNA. Translation: EAW76156.1.
CH471077 Genomic DNA. Translation: EAW76157.1.
BC048210 mRNA. Translation: AAH48210.1.
BC080598 mRNA. Translation: AAH80598.1.
BC093405 mRNA. Translation: AAH93405.1.
BC150178 mRNA. Translation: AAI50179.1.
AF258787 mRNA. Translation: AAG49888.1.
CCDSiCCDS13268.1. [Q9BVI0-1]
RefSeqiNP_057520.2. NM_016436.4. [Q9BVI0-1]
XP_016883353.1. XM_017027864.1. [Q9BVI0-1]
XP_016883354.1. XM_017027865.1. [Q9BVI0-1]
XP_016883355.1. XM_017027866.1. [Q9BVI0-1]
XP_016883356.1. XM_017027867.1. [Q9BVI0-1]
UniGeneiHs.517044.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2LDMNMR-A84-147[»]
3P8DX-ray2.00A/B84-147[»]
3Q1JX-ray2.35A4-69[»]
3QIIX-ray2.30A83-150[»]
3SD4X-ray1.93A/B4-69[»]
5TBNNMR-A646-699[»]
ProteinModelPortaliQ9BVI0.
SMRiQ9BVI0.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi119393. 18 interactors.
IntActiQ9BVI0. 9 interactors.
MINTiMINT-2829252.
STRINGi9606.ENSP00000363124.

PTM databases

iPTMnetiQ9BVI0.
PhosphoSitePlusiQ9BVI0.

Polymorphism and mutation databases

BioMutaiPHF20.
DMDMi32699605.

Proteomic databases

EPDiQ9BVI0.
MaxQBiQ9BVI0.
PaxDbiQ9BVI0.
PeptideAtlasiQ9BVI0.
PRIDEiQ9BVI0.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000374012; ENSP00000363124; ENSG00000025293. [Q9BVI0-1]
GeneIDi51230.
KEGGihsa:51230.
UCSCiuc002xek.2. human. [Q9BVI0-1]

Organism-specific databases

CTDi51230.
DisGeNETi51230.
GeneCardsiPHF20.
HGNCiHGNC:16098. PHF20.
HPAiHPA029619.
HPA029620.
HPA029621.
MIMi610335. gene.
neXtProtiNX_Q9BVI0.
OpenTargetsiENSG00000025293.
PharmGKBiPA25644.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiENOG410IMXB. Eukaryota.
ENOG410XX7Z. LUCA.
GeneTreeiENSGT00390000006451.
HOVERGENiHBG053586.
InParanoidiQ9BVI0.
KOiK18402.
OMAiCYQKPRT.
OrthoDBiEOG091G01T4.
PhylomeDBiQ9BVI0.
TreeFamiTF106475.

Enzyme and pathway databases

ReactomeiR-HSA-3214847. HATs acetylate histones.
R-HSA-6804759. Regulation of TP53 Activity through Association with Co-factors.
SIGNORiQ9BVI0.

Miscellaneous databases

ChiTaRSiPHF20. human.
EvolutionaryTraceiQ9BVI0.
GeneWikiiPHF20.
GenomeRNAii51230.
PROiQ9BVI0.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000025293.
CleanExiHS_PHF20.
ExpressionAtlasiQ9BVI0. baseline and differential.
GenevisibleiQ9BVI0. HS.

Family and domain databases

Gene3Di3.30.40.10. 1 hit.
InterProiIPR022255. DUF3776.
IPR002999. Tudor.
IPR019786. Zinc_finger_PHD-type_CS.
IPR007087. Znf_C2H2.
IPR011011. Znf_FYVE_PHD.
IPR001965. Znf_PHD.
IPR013083. Znf_RING/FYVE/PHD.
[Graphical view]
PfamiPF12618. DUF3776. 1 hit.
[Graphical view]
SMARTiSM00249. PHD. 1 hit.
SM00333. TUDOR. 2 hits.
[Graphical view]
SUPFAMiSSF57903. SSF57903. 1 hit.
PROSITEiPS01359. ZF_PHD_1. 1 hit.
PS00028. ZINC_FINGER_C2H2_1. 1 hit.
PS50157. ZINC_FINGER_C2H2_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPHF20_HUMAN
AccessioniPrimary (citable) accession number: Q9BVI0
Secondary accession number(s): A7E235
, B2RB56, E1P5S3, Q566Q2, Q5JWY9, Q66K49, Q9BWV4, Q9BXA3, Q9BZW3, Q9H421, Q9H4J6, Q9NZ22
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 11, 2003
Last sequence update: July 11, 2003
Last modified: November 30, 2016
This is version 155 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

Antibodies against PHF20 are present in sera from patients with hepatocellular carcinoma, glioblastoma and childhood medulloblastula.

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 20
    Human chromosome 20: 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.