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Protein

Transcription initiation factor TFIID subunit 1

Gene

Taf1

Organism
Mus musculus (Mouse)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Largest component and core scaffold of the TFIID basal transcription factor complex (PubMed:10438527). Contains novel N- and C-terminal Ser/Thr kinase domains which can autophosphorylate or transphosphorylate other transcription factors. Phosphorylates TP53 on 'Thr-55' which leads to MDM2-mediated degradation of TP53. Phosphorylates GTF2A1 and GTF2F1 on Ser residues. Possesses DNA-binding activity. Essential for progression of the G1 phase of the cell cycle. Exhibits histone acetyltransferase activity towards histones H3 and H4.By similarity1 Publication

Catalytic activityi

ATP + a protein = ADP + a phosphoprotein.
Acetyl-CoA + [histone] = CoA + acetyl-[histone].

Cofactori

Mg2+By similarity

Enzyme regulationi

Autophosphorylates on Ser residues. Inhibited by retinoblastoma tumor suppressor protein, RB1. Binding to TAF1 or CIITA inhibits the histone acetyltransferase activity.By similarity

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
DNA bindingi1216 – 1294HMG boxBy similarityAdd BLAST79

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Acyltransferase, Kinase, Serine/threonine-protein kinase, Transferase

Keywords - Biological processi

Cell cycle, Transcription, Transcription regulation

Keywords - Ligandi

ATP-binding, DNA-binding, Nucleotide-binding

Enzyme and pathway databases

ReactomeiR-MMU-674695. RNA Polymerase II Pre-transcription Events.
R-MMU-6804756. Regulation of TP53 Activity through Phosphorylation.
R-MMU-73776. RNA Polymerase II Promoter Escape.
R-MMU-73779. RNA Polymerase II Transcription Pre-Initiation And Promoter Opening.
R-MMU-75953. RNA Polymerase II Transcription Initiation.
R-MMU-76042. RNA Polymerase II Transcription Initiation And Promoter Clearance.

Names & Taxonomyi

Protein namesi
Recommended name:
Transcription initiation factor TFIID subunit 1 (EC:2.3.1.48, EC:2.7.11.1)
Alternative name(s):
Cell cycle gene 1 protein
TBP-associated factor 250 kDa
Short name:
p250
Transcription initiation factor TFIID 250 kDa subunit
Short name:
TAF(II)250
Short name:
TAFII-250
Short name:
TAFII250
Gene namesi
Name:Taf1
Synonyms:Ccg1
OrganismiMus musculus (Mouse)
Taxonomic identifieri10090 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeMusMus
Proteomesi
  • UP000000589 Componenti: Chromosome X

Organism-specific databases

MGIiMGI:1336878. Taf1.

Subcellular locationi

  • Nucleus By similarity

GO - Cellular componenti

  • MLL1 complex Source: UniProtKB
  • nuclear chromatin Source: MGI
  • nucleoplasm Source: MGI
  • nucleus Source: MGI
  • pronucleus Source: MGI
  • transcription factor complex Source: MGI
  • transcription factor TFIID complex Source: MGI
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00002785241 – 1891Transcription initiation factor TFIID subunit 1Add BLAST1891

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei328Phosphoserine; by autocatalysisBy similarity1
Modified residuei565N6-acetyllysineCombined sources1
Modified residuei1690PhosphoserineCombined sources1
Modified residuei1693PhosphoserineCombined sources1
Modified residuei1799PhosphoserineCombined sources1
Modified residuei1802PhosphoserineCombined sources1
Modified residuei1820PhosphoserineCombined sources1
Modified residuei1847PhosphoserineBy similarity1

Post-translational modificationi

Phosphorylated by casein kinase II in vitro.By similarity

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

PaxDbiQ80UV9.
PeptideAtlasiQ80UV9.
PRIDEiQ80UV9.

PTM databases

iPTMnetiQ80UV9.
PhosphoSitePlusiQ80UV9.

Expressioni

Gene expression databases

BgeeiENSMUSG00000031314.
ExpressionAtlasiQ80UV9. baseline and differential.
GenevisibleiQ80UV9. MM.

Interactioni

Subunit structurei

TAF1 is the largest component of transcription factor TFIID that is composed of TBP and a variety of TBP-associated factors (PubMed:10438527). TAF1, when part of the TFIID complex, interacts with C-terminus of TP53. Part of a TFIID-containing RNA polymerase II pre-initiation complex that is composed of TBP and at least GTF2A1, GTF2A2, GTF2E1, GTF2E2, GTF2F1, GTF2H2, GTF2H3, GTF2H4, GTF2H5, GTF2B, TCEA1, ERCC2, ERCC3, TAF1, TAF2, TAF3, TAF4, TAF5, TAF6, TAF7, TAF8, TAF9, TAF10, TAF11, TAF12 and TAF13. Interacts with TAF7; the interaction is direct. Component of some MLL1/MLL complex, at least composed of the core components KMT2A/MLL1, ASH2L, HCFC1/HCF1, 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. RB1 interacts with the N-terminal domain of TAF1. Interacts with ASF1A and ASF1B. Interacts (via bromo domains) with acetylated lysine residues on the N-terminus of histone H1.4, H2A, H2B, H3 and H4 (in vitro) (By similarity).By similarity

GO - Molecular functioni

Protein-protein interaction databases

BioGridi234808. 2 interactors.
DIPiDIP-61093N.
STRINGi10090.ENSMUSP00000098895.

Structurei

3D structure databases

ProteinModelPortaliQ80UV9.
SMRiQ80UV9.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini1 – 435Protein kinase 1Add BLAST435
Domaini1418 – 1488Bromo 1PROSITE-ProRule annotationAdd BLAST71
Domaini1446 – 1891Protein kinase 2Add BLAST446
Domaini1541 – 1611Bromo 2PROSITE-ProRule annotationAdd BLAST71

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni538 – 997Histone acetyltransferase (HAT)By similarityAdd BLAST460
Regioni1363 – 1650Interaction with ASF1A and ASF1BBy similarityAdd BLAST288

Motif

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Motifi1372 – 1379Nuclear localization signalSequence analysis8

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi157 – 165Poly-Pro9
Compositional biasi204 – 211Poly-Ser8
Compositional biasi1848 – 1855Poly-Glu8

Sequence similaritiesi

Belongs to the TAF1 family.Curated
Contains 2 bromo domains.PROSITE-ProRule annotation
Contains 1 HMG box DNA-binding domain.Curated
Contains 2 protein kinase domains.Curated

Keywords - Domaini

Bromodomain, Repeat

Phylogenomic databases

eggNOGiKOG0008. Eukaryota.
COG5076. LUCA.
COG5179. LUCA.
GeneTreeiENSGT00390000012659.
HOVERGENiHBG050223.
InParanoidiQ80UV9.
KOiK03125.

Family and domain databases

Gene3Di1.10.1100.10. 1 hit.
1.20.920.10. 2 hits.
InterProiIPR001487. Bromodomain.
IPR018359. Bromodomain_CS.
IPR011177. TAF1_animal.
IPR009067. TAF_II_230-bd.
IPR022591. TFIID_sub1_DUF3591.
[Graphical view]
PfamiPF00439. Bromodomain. 2 hits.
PF12157. DUF3591. 1 hit.
PF09247. TBP-binding. 1 hit.
[Graphical view]
PIRSFiPIRSF003047. TAF1_animal. 1 hit.
PRINTSiPR00503. BROMODOMAIN.
SMARTiSM00297. BROMO. 2 hits.
[Graphical view]
SUPFAMiSSF47055. SSF47055. 1 hit.
SSF47370. SSF47370. 2 hits.
PROSITEiPS00633. BROMODOMAIN_1. 2 hits.
PS50014. BROMODOMAIN_2. 2 hits.
[Graphical view]

Sequences (3)i

Sequence statusi: Complete.

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

Isoform 1 (identifier: Q80UV9-1) [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
MGPGWAGLLQ DKGGGSPSVV MSDTDSDEES AGGGPFSLTG FLFGNINGAG
60 70 80 90 100
QLEGESVLDD ECKKHLAGLG ALGLGSLITE LTANEELSGS DGALVNDEGW
110 120 130 140 150
IRSREDAVDY SDINEVAEDE SRRYQQTMGS LQPLCHTDYD EDDYDADCED
160 170 180 190 200
IDCKLMPPPP PPPGPLKKEK DQDDITGVSE DGEGIILPSI IAPSSLASEK
210 220 230 240 250
VDFSSSSDSE SEMGPQDAAQ SESKDGQLTL PLAGIMQHDA TKLLPSVTEL
260 270 280 290 300
FPEFRPGKVL RFLRLFGPGK NVPSVWRSAR RKRKKKHREL IQEGQVQEEE
310 320 330 340 350
CSVELEVNQK SLWNYDYAPP PLPDQCLSDD EITMMAPVES KFSQSTGDTD
360 370 380 390 400
KVMDTKPRVA EWRYGPARLW YDMLGVPEDG SGFDYGFKMK KTEHESTIKC
410 420 430 440 450
NIMKKLRKLE ENSGVDLLAD ENFLMVTQLH WEDDIIWDGE DVKHKGTKPQ
460 470 480 490 500
RASLAGWLPS SMTRNAMAYN VQQGFTATLD DDKPWYSIFP IDNEDLVYGR
510 520 530 540 550
WEDNIIWDAQ NMPRILEPPV LTLDPNDENL ILEIPDEKEE ATSNSPSKEN
560 570 580 590 600
KKESSLKKSR ILLGKTGVIK EEPQQNMSQP EVKDPWNLSN DEYYYPKQQG
610 620 630 640 650
LRGTFGGNII QHSIPAVELR QPFFPTHMGP IKLRQFHRPP LKKYSFGALS
660 670 680 690 700
QPGPHSVQPL LKHIKKKAKM REQERQASGG GEMFFMRTPQ DLTGKDGDLI
710 720 730 740 750
LAEYSEENGP LMMQVGMATK IKNYYKRKPG KDPGAPDCKY GETVYCHTSP
760 770 780 790 800
FLGSLHPGQL LQAFENNLFR APIYLHKMPE SDFLIIRTRQ GYFIRELVDI
810 820 830 840 850
FVVGQQCPLF EVPGPNSKRA NTHIRDFLQV FIYRLFWKSK DRPRRIRMED
860 870 880 890 900
IKKAFPSHSE SSIRKRLKLC ADFKRTGMDS NWWVLKSDFR LPTEEEIRAM
910 920 930 940 950
VSPEQCCAYY SMIAAEQRLK DAGYGEKSFF APEEENEEDF QMKIDDEVRT
960 970 980 990 1000
APWNTTRAFI AAMKGKCLLE VTGVADPTGC GEGFSYVKIP NKPTQQKDDK
1010 1020 1030 1040 1050
EPQPVKKTVT GTDADLRRLS LKNAKQLLRK FGVPEEEIKK LSRWEVIDVV
1060 1070 1080 1090 1100
RTMSTEQARS GEGPMSKFAR GSRFSVAEHQ ERYKEECQRI FDLQNKVLSS
1110 1120 1130 1140 1150
TEVLSTDTDS SSAEDSDFEE MGKNIENMLQ NKKTSSQLSR EREEQERKEL
1160 1170 1180 1190 1200
QRMLLAAGSA AAGNNHRDDD TASVTSLNSS ATGRCLKIYR TFRDEEGKEY
1210 1220 1230 1240 1250
VRCETVRKAT VIDAYVRIRT TKDEEFIRKF ALFDEQHREE MRKERRRIQE
1260 1270 1280 1290 1300
QLRRLKRNQE KEKLKGPPEK KPKKMKERPD LKLKCGACGA IGHMRTNKFC
1310 1320 1330 1340 1350
PLYYQTNAPP SNPVAMTEEQ EEELEKTVIH NDNEELIKVE GTKIVLGKQL
1360 1370 1380 1390 1400
IESADEVRRK SLVLKFPKQQ LPPKKKRRVG TTVHCDYLNR PHKSIHRRRT
1410 1420 1430 1440 1450
DPMVTLSSIL ESIINDMRDL PNTYPFHTPV NAKVVKDYYK IITRPMDLQT
1460 1470 1480 1490 1500
LRENVRKRLY PSREEFREHL ELIVKNSATY NGPKHSLTQI SQSMLDLCDE
1510 1520 1530 1540 1550
KLKEKEDKLA RLEKAINPLL DDDDQVAFSF ILDNIVTQKM MAVPDSWPFH
1560 1570 1580 1590 1600
HPVNKKFVPD YYKVIVSPMD LETIRKNISK HKYQSRESFL DDVNLILANS
1610 1620 1630 1640 1650
VKYNGPESQY TKTAQEIVNV CHQTLTEYDE HLTQLEKDIC TAKEAALEEA
1660 1670 1680 1690 1700
ELESLDPMTP GPYTPQPPDL YDNNTSLSVS RDASVYQDES NLSVLDIPSA
1710 1720 1730 1740 1750
TSEKQLTQEG GDGDGDLADE EEGTVQQPQA SVLYEDLLMS EGEDDEEDAG
1760 1770 1780 1790 1800
SDEEGDNPFF AIQLSESGSD SDVESGSLRP KQPRVLQENT RMGMENEESM
1810 1820 1830 1840 1850
MSYEGDGGDA SRGLEDSNIS YGSYEEPDPK SNTQDTSFSS IGGYEVSEEE
1860 1870 1880 1890
EDEEEQRSGP SVLSQVHLSE DEEDSEDFHS IAGDTDLDSD E
Length:1,891
Mass (Da):214,419
Last modified:March 6, 2007 - v2
Checksum:i9A4EA0475BB3E885
GO
Isoform 2 (identifier: Q80UV9-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-962: Missing.

Note: No experimental confirmation available.
Show »
Length:929
Mass (Da):105,780
Checksum:iA92987089CF8811D
GO
Isoform 3 (identifier: Q80UV9-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     178-198: Missing.

Note: No experimental confirmation available.
Show »
Length:1,870
Mass (Da):212,382
Checksum:iC7C3C29E868C630F
GO

Sequence cautioni

The sequence BAC34383 differs from that shown. Reason: Erroneous initiation.Curated

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti217D → E in AAD23348 (PubMed:10070062).Curated1
Sequence conflicti221S → A in AAD23348 (PubMed:10070062).Curated1
Sequence conflicti261R → H in AAD23348 (PubMed:10070062).Curated1
Sequence conflicti289E → K in AAD23348 (PubMed:10070062).Curated1
Sequence conflicti867 – 868LK → EG in AAC62118 (PubMed:9751712).Curated2
Sequence conflicti876T → Q in AAD23349 (PubMed:10070062).Curated1
Sequence conflicti1302 – 1306LYYQT → AFVAS in AAC62118 (PubMed:9751712).Curated5
Sequence conflicti1358R → P in AAD23350 (PubMed:10070062).Curated1
Sequence conflicti1388L → F in AAD23350 (PubMed:10070062).Curated1
Sequence conflicti1450T → E in AAD23350 (PubMed:10070062).Curated1
Sequence conflicti1469 – 1470HL → QM in AAD23350 (PubMed:10070062).Curated2
Sequence conflicti1736D → N in AAH94568 (PubMed:15489334).Curated1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0233201 – 962Missing in isoform 2. 1 PublicationAdd BLAST962
Alternative sequenceiVSP_023321178 – 198Missing in isoform 3. 1 PublicationAdd BLAST21

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AL831722, AL806534 Genomic DNA. Translation: CAM20496.1.
AL831722, AL806534 Genomic DNA. Translation: CAM20497.1.
AL806534, AL831722 Genomic DNA. Translation: CAM21283.1.
AL806534, AL831722 Genomic DNA. Translation: CAM21284.1.
BC047418 mRNA. Translation: AAH47418.1.
BC094568 mRNA. Translation: AAH94568.1.
AK045586 mRNA. Translation: BAC32425.1.
AK046668 mRNA. Translation: BAC32828.1.
AK049826 mRNA. Translation: BAC33938.1.
AK050691 mRNA. Translation: BAC34383.1. Different initiation.
AK132088 mRNA. Translation: BAE20976.1.
AK143571 mRNA. Translation: BAE25442.1.
AF081115 mRNA. Translation: AAD23349.1.
AF081116 mRNA. Translation: AAD23348.1.
AF081117 mRNA. Translation: AAD23350.1.
AF022178 mRNA. Translation: AAC62118.1.
RefSeqiNP_001277658.1. NM_001290729.1.
XP_006528113.1. XM_006528050.3. [Q80UV9-1]
XP_006528115.1. XM_006528052.3. [Q80UV9-3]
UniGeneiMm.261750.

Genome annotation databases

EnsembliENSMUST00000118878; ENSMUSP00000112772; ENSMUSG00000031314. [Q80UV9-3]
GeneIDi270627.
KEGGimmu:270627.
UCSCiuc009txy.1. mouse. [Q80UV9-2]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AL831722, AL806534 Genomic DNA. Translation: CAM20496.1.
AL831722, AL806534 Genomic DNA. Translation: CAM20497.1.
AL806534, AL831722 Genomic DNA. Translation: CAM21283.1.
AL806534, AL831722 Genomic DNA. Translation: CAM21284.1.
BC047418 mRNA. Translation: AAH47418.1.
BC094568 mRNA. Translation: AAH94568.1.
AK045586 mRNA. Translation: BAC32425.1.
AK046668 mRNA. Translation: BAC32828.1.
AK049826 mRNA. Translation: BAC33938.1.
AK050691 mRNA. Translation: BAC34383.1. Different initiation.
AK132088 mRNA. Translation: BAE20976.1.
AK143571 mRNA. Translation: BAE25442.1.
AF081115 mRNA. Translation: AAD23349.1.
AF081116 mRNA. Translation: AAD23348.1.
AF081117 mRNA. Translation: AAD23350.1.
AF022178 mRNA. Translation: AAC62118.1.
RefSeqiNP_001277658.1. NM_001290729.1.
XP_006528113.1. XM_006528050.3. [Q80UV9-1]
XP_006528115.1. XM_006528052.3. [Q80UV9-3]
UniGeneiMm.261750.

3D structure databases

ProteinModelPortaliQ80UV9.
SMRiQ80UV9.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi234808. 2 interactors.
DIPiDIP-61093N.
STRINGi10090.ENSMUSP00000098895.

PTM databases

iPTMnetiQ80UV9.
PhosphoSitePlusiQ80UV9.

Proteomic databases

PaxDbiQ80UV9.
PeptideAtlasiQ80UV9.
PRIDEiQ80UV9.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSMUST00000118878; ENSMUSP00000112772; ENSMUSG00000031314. [Q80UV9-3]
GeneIDi270627.
KEGGimmu:270627.
UCSCiuc009txy.1. mouse. [Q80UV9-2]

Organism-specific databases

CTDi6872.
MGIiMGI:1336878. Taf1.

Phylogenomic databases

eggNOGiKOG0008. Eukaryota.
COG5076. LUCA.
COG5179. LUCA.
GeneTreeiENSGT00390000012659.
HOVERGENiHBG050223.
InParanoidiQ80UV9.
KOiK03125.

Enzyme and pathway databases

ReactomeiR-MMU-674695. RNA Polymerase II Pre-transcription Events.
R-MMU-6804756. Regulation of TP53 Activity through Phosphorylation.
R-MMU-73776. RNA Polymerase II Promoter Escape.
R-MMU-73779. RNA Polymerase II Transcription Pre-Initiation And Promoter Opening.
R-MMU-75953. RNA Polymerase II Transcription Initiation.
R-MMU-76042. RNA Polymerase II Transcription Initiation And Promoter Clearance.

Miscellaneous databases

ChiTaRSiTaf1. mouse.
PROiQ80UV9.
SOURCEiSearch...

Gene expression databases

BgeeiENSMUSG00000031314.
ExpressionAtlasiQ80UV9. baseline and differential.
GenevisibleiQ80UV9. MM.

Family and domain databases

Gene3Di1.10.1100.10. 1 hit.
1.20.920.10. 2 hits.
InterProiIPR001487. Bromodomain.
IPR018359. Bromodomain_CS.
IPR011177. TAF1_animal.
IPR009067. TAF_II_230-bd.
IPR022591. TFIID_sub1_DUF3591.
[Graphical view]
PfamiPF00439. Bromodomain. 2 hits.
PF12157. DUF3591. 1 hit.
PF09247. TBP-binding. 1 hit.
[Graphical view]
PIRSFiPIRSF003047. TAF1_animal. 1 hit.
PRINTSiPR00503. BROMODOMAIN.
SMARTiSM00297. BROMO. 2 hits.
[Graphical view]
SUPFAMiSSF47055. SSF47055. 1 hit.
SSF47370. SSF47370. 2 hits.
PROSITEiPS00633. BROMODOMAIN_1. 2 hits.
PS50014. BROMODOMAIN_2. 2 hits.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiTAF1_MOUSE
AccessioniPrimary (citable) accession number: Q80UV9
Secondary accession number(s): A2AM32
, A2AM33, O35361, Q3UPF3, Q3V223, Q505F9, Q8BQH8, Q8BQQ7, Q8BR59, Q8C7N8, Q9WTW9, Q9WTX0, Q9WTX1
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 6, 2007
Last sequence update: March 6, 2007
Last modified: November 30, 2016
This is version 104 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. MGD cross-references
    Mouse Genome Database (MGD) cross-references in UniProtKB/Swiss-Prot
  2. 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.