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Protein

Arginine-glutamic acid dipeptide repeats protein

Gene

RERE

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

Functioni

Plays a role as a transcriptional repressor during development. May play a role in the control of cell survival. Overexpression of RERE recruits BAX to the nucleus particularly to POD and triggers caspase-3 activation, leading to cell death.1 Publication

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri507 – 532GATA-typeAdd BLAST26

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Developmental protein, Repressor

Keywords - Biological processi

Transcription, Transcription regulation

Keywords - Ligandi

Metal-binding, Zinc

Enzyme and pathway databases

BioCyciZFISH:ENSG00000142599-MONOMER.

Names & Taxonomyi

Protein namesi
Recommended name:
Arginine-glutamic acid dipeptide repeats protein
Alternative name(s):
Atrophin-1-like protein
Atrophin-1-related protein
Gene namesi
Name:RERE
Synonyms:ARG, ARP, ATN1L, KIAA0458
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 1

Organism-specific databases

HGNCiHGNC:9965. RERE.

Subcellular locationi

GO - Cellular componenti

  • histone deacetylase complex Source: Ensembl
  • nucleus Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Involvement in diseasei

A chromosomal aberration involving RERE is found in the neuroblastoma cell line NGP. Translocation t(1;15)(p36.2;q24).

Organism-specific databases

DisGeNETi473.
OpenTargetsiENSG00000142599.
PharmGKBiPA34332.

Polymorphism and mutation databases

BioMutaiRERE.
DMDMi85540730.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00000835041 – 1566Arginine-glutamic acid dipeptide repeats proteinAdd BLAST1566

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei53PhosphoserineCombined sources1
Modified residuei56PhosphoserineCombined sources1
Modified residuei120PhosphothreonineCombined sources1
Modified residuei142PhosphoserineBy similarity1
Modified residuei304PhosphoserineCombined sources1
Modified residuei594PhosphoserineCombined sources1
Modified residuei600PhosphoserineCombined sources1
Modified residuei613PhosphoserineCombined sources1
Cross-linki637Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in SUMO2)Combined sources
Modified residuei642PhosphoserineCombined sources1
Modified residuei656PhosphoserineCombined sources1
Modified residuei675PhosphoserineCombined sources1
Modified residuei679PhosphoserineCombined sources1
Modified residuei1106PhosphoserineCombined sources1
Modified residuei1113PhosphoserineCombined sources1
Modified residuei1115PhosphoserineBy similarity1
Modified residuei1119PhosphothreonineCombined sources1
Modified residuei1158N6-acetyllysineBy similarity1
Modified residuei1259PhosphotyrosineCombined sources1
Modified residuei1266PhosphoserineCombined sources1

Keywords - PTMi

Acetylation, Isopeptide bond, Phosphoprotein, Ubl conjugation

Proteomic databases

EPDiQ9P2R6.
MaxQBiQ9P2R6.
PaxDbiQ9P2R6.
PeptideAtlasiQ9P2R6.
PRIDEiQ9P2R6.

PTM databases

iPTMnetiQ9P2R6.
PhosphoSitePlusiQ9P2R6.

Expressioni

Tissue specificityi

Widely expressed. Expressed in tumor cell lines.3 Publications

Gene expression databases

BgeeiENSG00000142599.
CleanExiHS_RERE.
ExpressionAtlasiQ9P2R6. baseline and differential.
GenevisibleiQ9P2R6. HS.

Organism-specific databases

HPAiHPA024093.

Interactioni

Subunit structurei

Interacts with HDAC1 (By similarity). Interacts with ATN1. Interaction with ATN1 is improved when the poly-Gln region of ATN1 is extended. Interacts with FAT1.By similarity2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
ATN1P542593EBI-948076,EBI-945980
EHMT2Q96KQ73EBI-948076,EBI-744366

GO - Molecular functioni

  • poly-glutamine tract binding Source: ProtInc

Protein-protein interaction databases

BioGridi106963. 30 interactors.
DIPiDIP-47606N.
IntActiQ9P2R6. 25 interactors.
MINTiMINT-2820762.
STRINGi9606.ENSP00000338629.

Structurei

Secondary structure

11566
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi398 – 410Combined sources13
Helixi415 – 421Combined sources7
Helixi428 – 439Combined sources12

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2YQKNMR-A392-441[»]
ProteinModelPortaliQ9P2R6.
SMRiQ9P2R6.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ9P2R6.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini103 – 283BAHPROSITE-ProRule annotationAdd BLAST181
Domaini284 – 387ELM2PROSITE-ProRule annotationAdd BLAST104
Domaini391 – 443SANTPROSITE-ProRule annotationAdd BLAST53

Coiled coil

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Coiled coili1156 – 1211Sequence analysisAdd BLAST56

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi738 – 1118Pro-richAdd BLAST381
Compositional biasi1179 – 1204Arg/Glu-rich (mixed charge)Add BLAST26
Compositional biasi1300 – 1322Arg/Glu-rich (mixed charge)Add BLAST23
Compositional biasi1425 – 1445His-richAdd BLAST21
Compositional biasi1451 – 1510Pro-richAdd BLAST60

Domaini

The interaction with ATN1 is mediated by the coiled coil domain.

Sequence similaritiesi

Contains 1 BAH domain.PROSITE-ProRule annotation
Contains 1 ELM2 domain.PROSITE-ProRule annotation
Contains 1 GATA-type zinc finger.Curated
Contains 1 SANT domain.PROSITE-ProRule annotation

Zinc finger

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri507 – 532GATA-typeAdd BLAST26

Keywords - Domaini

Coiled coil, Zinc-finger

Phylogenomic databases

eggNOGiKOG2133. Eukaryota.
ENOG410ZIND. LUCA.
GeneTreeiENSGT00580000081398.
HOGENOMiHOG000231091.
HOVERGENiHBG079774.
InParanoidiQ9P2R6.
KOiK05628.
OMAiMPHIKPP.
OrthoDBiEOG091G0O1H.
PhylomeDBiQ9P2R6.
TreeFamiTF328554.

Family and domain databases

Gene3Di3.30.50.10. 1 hit.
InterProiIPR002951. Atrophin-like.
IPR001025. BAH_dom.
IPR000949. ELM2_dom.
IPR009057. Homeodomain-like.
IPR001005. SANT/Myb.
IPR017884. SANT_dom.
IPR000679. Znf_GATA.
IPR013088. Znf_NHR/GATA.
[Graphical view]
PfamiPF03154. Atrophin-1. 1 hit.
PF01426. BAH. 1 hit.
PF01448. ELM2. 1 hit.
PF00320. GATA. 1 hit.
[Graphical view]
SMARTiSM00439. BAH. 1 hit.
SM01189. ELM2. 1 hit.
SM00717. SANT. 1 hit.
SM00401. ZnF_GATA. 1 hit.
[Graphical view]
SUPFAMiSSF46689. SSF46689. 1 hit.
PROSITEiPS51038. BAH. 1 hit.
PS51156. ELM2. 1 hit.
PS51293. SANT. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

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

Note: Additional isoforms seem to exist.
Isoform 1 (identifier: Q9P2R6-1) [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
MTADKDKDKD KEKDRDRDRD REREKRDKAR ESENSRPRRS CTLEGGAKNY
60 70 80 90 100
AESDHSEDED NDNNSATAEE STKKNKKKPP KKKSRYERTD TGEITSYITE
110 120 130 140 150
DDVVYRPGDC VYIESRRPNT PYFICSIQDF KLVHNSQACC RSPTPALCDP
160 170 180 190 200
PACSLPVASQ PPQHLSEAGR GPVGSKRDHL LMNVKWYYRQ SEVPDSVYQH
210 220 230 240 250
LVQDRHNEND SGRELVITDP VIKNRELFIS DYVDTYHAAA LRGKCNISHF
260 270 280 290 300
SDIFAAREFK ARVDSFFYIL GYNPETRRLN STQGEIRVGP SHQAKLPDLQ
310 320 330 340 350
PFPSPDGDTV TQHEELVWMP GVNDCDLLMY LRAARSMAAF AGMCDGGSTE
360 370 380 390 400
DGCVAASRDD TTLNALNTLH ESGYDAGKAL QRLVKKPVPK LIEKCWTEDE
410 420 430 440 450
VKRFVKGLRQ YGKNFFRIRK ELLPNKETGE LITFYYYWKK TPEAASSRAH
460 470 480 490 500
RRHRRQAVFR RIKTRTASTP VNTPSRPPSS EFLDLSSASE DDFDSEDSEQ
510 520 530 540 550
ELKGYACRHC FTTTSKDWHH GGRENILLCT DCRIHFKKYG ELPPIEKPVD
560 570 580 590 600
PPPFMFKPVK EEDDGLSGKH SMRTRRSRGS MSTLRSGRKK QPASPDGRTS
610 620 630 640 650
PINEDIRSSG RNSPSAASTS SNDSKAETVK KSAKKVKEEA SSPLKSNKRQ
660 670 680 690 700
REKVASDTEE ADRTSSKKTK TQEISRPNSP SEGEGESSDS RSVNDEGSSD
710 720 730 740 750
PKDIDQDNRS TSPSIPSPQD NESDSDSSAQ QQMLQAQPPA LQAPTGVTPA
760 770 780 790 800
PSSAPPGTPQ LPTPGPTPSA TAVPPQGSPT ASQAPNQPQA PTAPVPHTHI
810 820 830 840 850
QQAPALHPQR PPSPHPPPHP SPHPPLQPLT GSAGQPSAPS HAQPPLHGQG
860 870 880 890 900
PPGPHSLQAG PLLQHPGPPQ PFGLPPQASQ GQAPLGTSPA AAYPHTSLQL
910 920 930 940 950
PASQSALQSQ QPPREQPLPP APLAMPHIKP PPTTPIPQLP APQAHKHPPH
960 970 980 990 1000
LSGPSPFSMN ANLPPPPALK PLSSLSTHHP PSAHPPPLQL MPQSQPLPSS
1010 1020 1030 1040 1050
PAQPPGLTQS QNLPPPPASH PPTGLHQVAP QPPFAQHPFV PGGPPPITPP
1060 1070 1080 1090 1100
TCPSTSTPPA GPGTSAQPPC SGAAASGGSI AGGSSCPLPT VQIKEEALDD
1110 1120 1130 1140 1150
AEEPESPPPP PRSPSPEPTV VDTPSHASQS ARFYKHLDRG YNSCARTDLY
1160 1170 1180 1190 1200
FMPLAGSKLA KKREEAIEKA KREAEQKARE EREREKEKEK ERERERERER
1210 1220 1230 1240 1250
EAERAAKASS SAHEGRLSDP QLSGPGHMRP SFEPPPTTIA AVPPYIGPDT
1260 1270 1280 1290 1300
PALRTLSEYA RPHVMSPTNR NHPFYMPLNP TDPLLAYHMP GLYNVDPTIR
1310 1320 1330 1340 1350
ERELREREIR EREIRERELR ERMKPGFEVK PPELDPLHPA ANPMEHFARH
1360 1370 1380 1390 1400
SALTIPPTAG PHPFASFHPG LNPLERERLA LAGPQLRPEM SYPDRLAAER
1410 1420 1430 1440 1450
IHAERMASLT SDPLARLQMF NVTPHHHQHS HIHSHLHLHQ QDPLHQGSAG
1460 1470 1480 1490 1500
PVHPLVDPLT AGPHLARFPY PPGTLPNPLL GQPPHEHEML RHPVFGTPYP
1510 1520 1530 1540 1550
RDLPGAIPPP MSAAHQLQAM HAQSAELQRL AMEQQWLHGH PHMHGGHLPS
1560
QEDYYSRLKK EGDKQL
Length:1,566
Mass (Da):172,424
Last modified:January 10, 2006 - v2
Checksum:iECA4A22026E3E96F
GO
Isoform 2 (identifier: Q9P2R6-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-554: Missing.

Show »
Length:1,012
Mass (Da):109,048
Checksum:i54B60DCBF0FB85FE
GO

Sequence cautioni

The sequence AAC31120 differs from that shown. Reason: Frameshift at positions 588 and 596.Curated
The sequence AAD27584 differs from that shown. Reason: Erroneous initiation.Curated

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti65S → G in BAA95898 (PubMed:10814707).Curated1
Sequence conflicti68A → T in BAA95898 (PubMed:10814707).Curated1
Sequence conflicti114 – 115ES → VC in BAA95898 (PubMed:10814707).Curated2
Sequence conflicti643P → L in AAC31120 (Ref. 3) Curated1
Sequence conflicti921A → G in BAA95898 (PubMed:10814707).Curated1
Sequence conflicti940P → A in BAA95898 (PubMed:10814707).Curated1
Sequence conflicti957F → L in AAD27584 (PubMed:10729226).Curated1
Sequence conflicti977T → K no nucleotide entry (PubMed:11331249).Curated1
Sequence conflicti984H → N no nucleotide entry (PubMed:11331249).Curated1
Sequence conflicti1009 – 1011QSQ → RTR in AAD27584 (PubMed:10729226).Curated3
Sequence conflicti1117E → D in AAD27584 (PubMed:10729226).Curated1
Sequence conflicti1272H → Q in AAD27584 (PubMed:10729226).Curated1
Sequence conflicti1489 – 1490ML → IV in BAA95898 (PubMed:10814707).Curated2
Sequence conflicti1529R → K in AAD27584 (PubMed:10729226).Curated1
Sequence conflicti1536W → C in AAD27584 (PubMed:10729226).Curated1
Sequence conflicti1543M → R in AAD27584 (PubMed:10729226).Curated1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0168781 – 554Missing in isoform 2. 1 PublicationAdd BLAST554

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB036737 mRNA. Translation: BAA95898.1.
AF016005 mRNA. Translation: AAC31120.1. Frameshift.
AF041104
, AF041096, AF041097, AF041098, AF041099, AF041100, AF041101, AF041102, AF041103 Genomic DNA. Translation: AAC28264.1.
AL356072, AL096855, AL357713 Genomic DNA. Translation: CAH70516.1.
AL357713, AL096855, AL356072 Genomic DNA. Translation: CAH73433.1.
AL096855, AL356072, AL357713 Genomic DNA. Translation: CAI19208.1.
AB007927 mRNA. Translation: BAA32303.3.
AF118275 mRNA. Translation: AAD27584.1. Different initiation.
CCDSiCCDS41243.1. [Q9P2R6-2]
CCDS95.1. [Q9P2R6-1]
RefSeqiNP_001036146.1. NM_001042681.1. [Q9P2R6-1]
NP_001036147.1. NM_001042682.1. [Q9P2R6-2]
NP_036234.3. NM_012102.3. [Q9P2R6-1]
XP_005263521.1. XM_005263464.2. [Q9P2R6-1]
XP_016856847.1. XM_017001358.1. [Q9P2R6-1]
XP_016856848.1. XM_017001359.1. [Q9P2R6-1]
UniGeneiHs.463041.

Genome annotation databases

EnsembliENST00000337907; ENSP00000338629; ENSG00000142599. [Q9P2R6-1]
ENST00000400908; ENSP00000383700; ENSG00000142599. [Q9P2R6-1]
ENST00000476556; ENSP00000422246; ENSG00000142599. [Q9P2R6-2]
GeneIDi473.
KEGGihsa:473.
UCSCiuc001apd.4. human. [Q9P2R6-1]

Keywords - Coding sequence diversityi

Alternative splicing, Chromosomal rearrangement

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB036737 mRNA. Translation: BAA95898.1.
AF016005 mRNA. Translation: AAC31120.1. Frameshift.
AF041104
, AF041096, AF041097, AF041098, AF041099, AF041100, AF041101, AF041102, AF041103 Genomic DNA. Translation: AAC28264.1.
AL356072, AL096855, AL357713 Genomic DNA. Translation: CAH70516.1.
AL357713, AL096855, AL356072 Genomic DNA. Translation: CAH73433.1.
AL096855, AL356072, AL357713 Genomic DNA. Translation: CAI19208.1.
AB007927 mRNA. Translation: BAA32303.3.
AF118275 mRNA. Translation: AAD27584.1. Different initiation.
CCDSiCCDS41243.1. [Q9P2R6-2]
CCDS95.1. [Q9P2R6-1]
RefSeqiNP_001036146.1. NM_001042681.1. [Q9P2R6-1]
NP_001036147.1. NM_001042682.1. [Q9P2R6-2]
NP_036234.3. NM_012102.3. [Q9P2R6-1]
XP_005263521.1. XM_005263464.2. [Q9P2R6-1]
XP_016856847.1. XM_017001358.1. [Q9P2R6-1]
XP_016856848.1. XM_017001359.1. [Q9P2R6-1]
UniGeneiHs.463041.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2YQKNMR-A392-441[»]
ProteinModelPortaliQ9P2R6.
SMRiQ9P2R6.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi106963. 30 interactors.
DIPiDIP-47606N.
IntActiQ9P2R6. 25 interactors.
MINTiMINT-2820762.
STRINGi9606.ENSP00000338629.

PTM databases

iPTMnetiQ9P2R6.
PhosphoSitePlusiQ9P2R6.

Polymorphism and mutation databases

BioMutaiRERE.
DMDMi85540730.

Proteomic databases

EPDiQ9P2R6.
MaxQBiQ9P2R6.
PaxDbiQ9P2R6.
PeptideAtlasiQ9P2R6.
PRIDEiQ9P2R6.

Protocols and materials databases

DNASUi473.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000337907; ENSP00000338629; ENSG00000142599. [Q9P2R6-1]
ENST00000400908; ENSP00000383700; ENSG00000142599. [Q9P2R6-1]
ENST00000476556; ENSP00000422246; ENSG00000142599. [Q9P2R6-2]
GeneIDi473.
KEGGihsa:473.
UCSCiuc001apd.4. human. [Q9P2R6-1]

Organism-specific databases

CTDi473.
DisGeNETi473.
GeneCardsiRERE.
HGNCiHGNC:9965. RERE.
HPAiHPA024093.
MIMi605226. gene.
neXtProtiNX_Q9P2R6.
OpenTargetsiENSG00000142599.
PharmGKBiPA34332.
HUGEiSearch...
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG2133. Eukaryota.
ENOG410ZIND. LUCA.
GeneTreeiENSGT00580000081398.
HOGENOMiHOG000231091.
HOVERGENiHBG079774.
InParanoidiQ9P2R6.
KOiK05628.
OMAiMPHIKPP.
OrthoDBiEOG091G0O1H.
PhylomeDBiQ9P2R6.
TreeFamiTF328554.

Enzyme and pathway databases

BioCyciZFISH:ENSG00000142599-MONOMER.

Miscellaneous databases

ChiTaRSiRERE. human.
EvolutionaryTraceiQ9P2R6.
GeneWikiiRERE.
GenomeRNAii473.
PROiQ9P2R6.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000142599.
CleanExiHS_RERE.
ExpressionAtlasiQ9P2R6. baseline and differential.
GenevisibleiQ9P2R6. HS.

Family and domain databases

Gene3Di3.30.50.10. 1 hit.
InterProiIPR002951. Atrophin-like.
IPR001025. BAH_dom.
IPR000949. ELM2_dom.
IPR009057. Homeodomain-like.
IPR001005. SANT/Myb.
IPR017884. SANT_dom.
IPR000679. Znf_GATA.
IPR013088. Znf_NHR/GATA.
[Graphical view]
PfamiPF03154. Atrophin-1. 1 hit.
PF01426. BAH. 1 hit.
PF01448. ELM2. 1 hit.
PF00320. GATA. 1 hit.
[Graphical view]
SMARTiSM00439. BAH. 1 hit.
SM01189. ELM2. 1 hit.
SM00717. SANT. 1 hit.
SM00401. ZnF_GATA. 1 hit.
[Graphical view]
SUPFAMiSSF46689. SSF46689. 1 hit.
PROSITEiPS51038. BAH. 1 hit.
PS51156. ELM2. 1 hit.
PS51293. SANT. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiRERE_HUMAN
AccessioniPrimary (citable) accession number: Q9P2R6
Secondary accession number(s): O43393
, O75046, O75359, Q5VXL9, Q6P6B9, Q9Y2W4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: January 10, 2006
Last sequence update: January 10, 2006
Last modified: November 30, 2016
This is version 151 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, Reference proteome

Documents

  1. Human chromosome 1
    Human chromosome 1: entries, gene names and cross-references to MIM
  2. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  3. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  4. 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.