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Protein

Tubulin alpha-1B chain

Gene

TUBA1B

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

Functioni

Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain.

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sitei451 – 4511Involved in polymerization

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi142 – 1487GTPSequence Analysis

GO - Molecular functioni

  • double-stranded RNA binding Source: MGI
  • GTPase activity Source: InterPro
  • GTP binding Source: UniProtKB-KW
  • structural constituent of cytoskeleton Source: Ensembl
  • structural molecule activity Source: BHF-UCL
  • ubiquitin protein ligase binding Source: ParkinsonsUK-UCL

GO - Biological processi

  • 'de novo' posttranslational protein folding Source: Reactome
  • cell division Source: BHF-UCL
  • cellular protein metabolic process Source: Reactome
  • cellular response to interleukin-4 Source: Ensembl
  • cytoskeleton-dependent intracellular transport Source: BHF-UCL
  • microtubule-based process Source: BHF-UCL
  • microtubule cytoskeleton organization Source: Ensembl
  • protein folding Source: Reactome
  • protein polymerization Source: InterPro
Complete GO annotation...

Keywords - Ligandi

GTP-binding, Nucleotide-binding

Enzyme and pathway databases

ReactomeiREACT_11039. Microtubule-dependent trafficking of connexons from Golgi to the plasma membrane.
REACT_121399. MHC class II antigen presentation.
REACT_147867. Translocation of GLUT4 to the plasma membrane.
REACT_150425. Resolution of Sister Chromatid Cohesion.
REACT_150471. Separation of Sister Chromatids.
REACT_15510. Recruitment of NuMA to mitotic centrosomes.
REACT_16956. Formation of tubulin folding intermediates by CCT/TriC.
REACT_16967. Post-chaperonin tubulin folding pathway.
REACT_22365. Recycling pathway of L1.
REACT_25201. Kinesins.
REACT_268024. Intraflagellar transport.
REACT_268265. Assembly of the primary cilium.
REACT_268323. Hedgehog 'off' state.
REACT_355252. RHO GTPases Activate Formins.
REACT_355469. RHO GTPases activate IQGAPs.
REACT_682. Mitotic Prometaphase.
REACT_9509. Gap junction assembly.

Names & Taxonomyi

Protein namesi
Recommended name:
Tubulin alpha-1B chain
Alternative name(s):
Alpha-tubulin ubiquitous
Tubulin K-alpha-1
Tubulin alpha-ubiquitous chain
Gene namesi
Name:TUBA1B
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 12

Organism-specific databases

HGNCiHGNC:18809. TUBA1B.

Subcellular locationi

GO - Cellular componenti

  • cytoplasmic microtubule Source: Ensembl
  • extracellular exosome Source: UniProtKB
  • microtubule Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Cytoskeleton, Microtubule

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA162407332.

Polymorphism and mutation databases

BioMutaiTUBA1B.
DMDMi55977474.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 451451Tubulin alpha-1B chainPRO_0000048108Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei48 – 481Phosphoserine1 Publication
Modified residuei83 – 831Nitrated tyrosineBy similarity
Modified residuei232 – 2321Phosphoserine1 Publication
Modified residuei282 – 2821Nitrated tyrosineBy similarity
Cross-linki326 – 326Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)
Modified residuei339 – 3391Omega-N-methylarginine1 Publication
Cross-linki370 – 370Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)
Modified residuei432 – 4321PhosphotyrosineBy similarity
Modified residuei439 – 4391PhosphoserineBy similarity

Post-translational modificationi

Undergoes a tyrosination/detyrosination cycle, the cyclic removal and re-addition of a C-terminal tyrosine residue by the enzymes tubulin tyrosine carboxypeptidase (TTCP) and tubulin tyrosine ligase (TTL), respectively.By similarity
Some glutamate residues at the C-terminus are polyglutamylated. This modification occurs exclusively on glutamate residues and results in polyglutamate chains on the gamma-carboxyl group. Also monoglycylated but not polyglycylated due to the absence of functional TTLL10 in human. Monoglycylation is mainly limited to tubulin incorporated into axonemes (cilia and flagella) whereas glutamylation is prevalent in neuronal cells, centrioles, axonemes, and the mitotic spindle. Both modifications can coexist on the same protein on adjacent residues, and lowering glycylation levels increases polyglutamylation, and reciprocally. The precise function of such modifications is still unclear but they regulate the assembly and dynamics of axonemal microtubules (Probable).1 Publication
Acetylation of alpha chains at Lys-40 stabilizes microtubules and affects affinity and processivity of microtubule motors. This modification has a role in multiple cellular functions, ranging from cell motility, cell cycle progression or cell differentiation to intracellular trafficking and signaling (By similarity).By similarity

Keywords - PTMi

Acetylation, Isopeptide bond, Methylation, Nitration, Phosphoprotein, Ubl conjugation

Proteomic databases

MaxQBiP68363.
PaxDbiP68363.
PRIDEiP68363.

2D gel databases

OGPiP68363.
SWISS-2DPAGEP68363.

PTM databases

PhosphoSiteiP68363.

Expressioni

Gene expression databases

BgeeiP68363.
CleanExiHS_TUBA1B.
ExpressionAtlasiP68363. baseline and differential.
GenevestigatoriP68363.

Organism-specific databases

HPAiCAB011513.
HPA039247.
HPA043684.
HPA063394.

Interactioni

Subunit structurei

Dimer of alpha and beta chains. A typical microtubule is a hollow water-filled tube with an outer diameter of 25 nm and an inner diameter of 15 nM. Alpha-beta heterodimers associate head-to-tail to form protofilaments running lengthwise along the microtubule wall with the beta-tubulin subunit facing the microtubule plus end conferring a structural polarity. Microtubules usually have 13 protofilaments but different protofilament numbers can be found in some organisms and specialized cells.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
AGTRAPQ6RW133EBI-487083,EBI-741181
EBNA-LPQ8AZK73EBI-487083,EBI-1185167From a different organism.
TUBB3Q135093EBI-487083,EBI-350989

Protein-protein interaction databases

BioGridi115651. 90 interactions.
IntActiP68363. 25 interactions.
MINTiMINT-4998849.
STRINGi9606.ENSP00000336799.

Structurei

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2E4HNMR-B416-451[»]
ProteinModelPortaliP68363.
SMRiP68363. Positions 1-440.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP68363.

Family & Domainsi

Sequence similaritiesi

Belongs to the tubulin family.Curated

Phylogenomic databases

eggNOGiCOG5023.
GeneTreeiENSGT00760000119060.
HOGENOMiHOG000165711.
HOVERGENiHBG000089.
InParanoidiP68363.
KOiK07374.
OMAiPRPSFAN.
OrthoDBiEOG7TBC1W.
PhylomeDBiP68363.
TreeFamiTF300314.

Family and domain databases

Gene3Di1.10.287.600. 1 hit.
3.30.1330.20. 1 hit.
3.40.50.1440. 1 hit.
InterProiIPR002452. Alpha_tubulin.
IPR008280. Tub_FtsZ_C.
IPR000217. Tubulin.
IPR018316. Tubulin/FtsZ_2-layer-sand-dom.
IPR023123. Tubulin_C.
IPR017975. Tubulin_CS.
IPR003008. Tubulin_FtsZ_GTPase.
[Graphical view]
PANTHERiPTHR11588. PTHR11588. 1 hit.
PfamiPF00091. Tubulin. 1 hit.
PF03953. Tubulin_C. 1 hit.
[Graphical view]
PRINTSiPR01162. ALPHATUBULIN.
PR01161. TUBULIN.
SMARTiSM00864. Tubulin. 1 hit.
SM00865. Tubulin_C. 1 hit.
[Graphical view]
SUPFAMiSSF52490. SSF52490. 1 hit.
SSF55307. SSF55307. 1 hit.
PROSITEiPS00227. TUBULIN. 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: P68363-1) [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
MRECISIHVG QAGVQIGNAC WELYCLEHGI QPDGQMPSDK TIGGGDDSFN
60 70 80 90 100
TFFSETGAGK HVPRAVFVDL EPTVIDEVRT GTYRQLFHPE QLITGKEDAA
110 120 130 140 150
NNYARGHYTI GKEIIDLVLD RIRKLADQCT GLQGFLVFHS FGGGTGSGFT
160 170 180 190 200
SLLMERLSVD YGKKSKLEFS IYPAPQVSTA VVEPYNSILT THTTLEHSDC
210 220 230 240 250
AFMVDNEAIY DICRRNLDIE RPTYTNLNRL ISQIVSSITA SLRFDGALNV
260 270 280 290 300
DLTEFQTNLV PYPRIHFPLA TYAPVISAEK AYHEQLSVAE ITNACFEPAN
310 320 330 340 350
QMVKCDPRHG KYMACCLLYR GDVVPKDVNA AIATIKTKRS IQFVDWCPTG
360 370 380 390 400
FKVGINYQPP TVVPGGDLAK VQRAVCMLSN TTAIAEAWAR LDHKFDLMYA
410 420 430 440 450
KRAFVHWYVG EGMEEGEFSE AREDMAALEK DYEEVGVDSV EGEGEEEGEE

Y
Length:451
Mass (Da):50,152
Last modified:August 13, 1987 - v1
Checksum:i94355B4EC2086429
GO
Isoform 2 (identifier: P68363-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     108-223: Missing.

Note: No experimental confirmation available.

Show »
Length:335
Mass (Da):37,218
Checksum:iCEC8DAFE68516D27
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti131 – 1311G → R in AAA91576 (PubMed:6646120).Curated
Sequence conflicti290 – 2901E → D in AAA91576 (PubMed:6646120).Curated
Sequence conflicti308 – 3081R → G in AAA91576 (PubMed:6646120).Curated
Sequence conflicti340 – 3401S → T in AAA91576 (PubMed:6646120).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei108 – 223116Missing in isoform 2. 1 PublicationVSP_055764Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
K00558 mRNA. Translation: AAA91576.1.
AF081484 mRNA. Translation: AAC31959.1.
DQ400107 mRNA. Translation: ABD60581.1.
BC000696 mRNA. Translation: AAH00696.1.
BC001128 mRNA. Translation: AAH01128.1.
BC006379 mRNA. Translation: AAH06379.1.
BC006481 mRNA. Translation: AAH06481.1.
BC008659 mRNA. Translation: AAH08659.1.
BC009314 mRNA. Translation: AAH09314.1.
BC009509 mRNA. Translation: AAH09509.1.
BC009512 mRNA. Translation: AAH09512.1.
BC009513 mRNA. Translation: AAH09513.1.
BC010494 mRNA. Translation: AAH10494.1.
BC011572 mRNA. Translation: AAH11572.1.
BC015883 mRNA. Translation: AAH15883.1.
BC017004 mRNA. Translation: AAH17004.1.
BC021564 mRNA. Translation: AAH21564.1.
BC030820 mRNA. Translation: AAH30820.1.
BC071904 mRNA. Translation: AAH71904.1.
CCDSiCCDS31792.1. [P68363-1]
PIRiI77403.
RefSeqiNP_006073.2. NM_006082.2. [P68363-1]
UniGeneiHs.524390.

Genome annotation databases

EnsembliENST00000336023; ENSP00000336799; ENSG00000123416. [P68363-1]
GeneIDi10376.
KEGGihsa:10376.
UCSCiuc001rtl.3. human. [P68363-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
K00558 mRNA. Translation: AAA91576.1.
AF081484 mRNA. Translation: AAC31959.1.
DQ400107 mRNA. Translation: ABD60581.1.
BC000696 mRNA. Translation: AAH00696.1.
BC001128 mRNA. Translation: AAH01128.1.
BC006379 mRNA. Translation: AAH06379.1.
BC006481 mRNA. Translation: AAH06481.1.
BC008659 mRNA. Translation: AAH08659.1.
BC009314 mRNA. Translation: AAH09314.1.
BC009509 mRNA. Translation: AAH09509.1.
BC009512 mRNA. Translation: AAH09512.1.
BC009513 mRNA. Translation: AAH09513.1.
BC010494 mRNA. Translation: AAH10494.1.
BC011572 mRNA. Translation: AAH11572.1.
BC015883 mRNA. Translation: AAH15883.1.
BC017004 mRNA. Translation: AAH17004.1.
BC021564 mRNA. Translation: AAH21564.1.
BC030820 mRNA. Translation: AAH30820.1.
BC071904 mRNA. Translation: AAH71904.1.
CCDSiCCDS31792.1. [P68363-1]
PIRiI77403.
RefSeqiNP_006073.2. NM_006082.2. [P68363-1]
UniGeneiHs.524390.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2E4HNMR-B416-451[»]
ProteinModelPortaliP68363.
SMRiP68363. Positions 1-440.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi115651. 90 interactions.
IntActiP68363. 25 interactions.
MINTiMINT-4998849.
STRINGi9606.ENSP00000336799.

Chemistry

ChEMBLiCHEMBL2095182.

PTM databases

PhosphoSiteiP68363.

Polymorphism and mutation databases

BioMutaiTUBA1B.
DMDMi55977474.

2D gel databases

OGPiP68363.
SWISS-2DPAGEP68363.

Proteomic databases

MaxQBiP68363.
PaxDbiP68363.
PRIDEiP68363.

Protocols and materials databases

DNASUi10376.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000336023; ENSP00000336799; ENSG00000123416. [P68363-1]
GeneIDi10376.
KEGGihsa:10376.
UCSCiuc001rtl.3. human. [P68363-1]

Organism-specific databases

CTDi10376.
GeneCardsiGC12M049523.
H-InvDBHIX0079488.
HGNCiHGNC:18809. TUBA1B.
HPAiCAB011513.
HPA039247.
HPA043684.
HPA063394.
MIMi602530. gene.
neXtProtiNX_P68363.
PharmGKBiPA162407332.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG5023.
GeneTreeiENSGT00760000119060.
HOGENOMiHOG000165711.
HOVERGENiHBG000089.
InParanoidiP68363.
KOiK07374.
OMAiPRPSFAN.
OrthoDBiEOG7TBC1W.
PhylomeDBiP68363.
TreeFamiTF300314.

Enzyme and pathway databases

ReactomeiREACT_11039. Microtubule-dependent trafficking of connexons from Golgi to the plasma membrane.
REACT_121399. MHC class II antigen presentation.
REACT_147867. Translocation of GLUT4 to the plasma membrane.
REACT_150425. Resolution of Sister Chromatid Cohesion.
REACT_150471. Separation of Sister Chromatids.
REACT_15510. Recruitment of NuMA to mitotic centrosomes.
REACT_16956. Formation of tubulin folding intermediates by CCT/TriC.
REACT_16967. Post-chaperonin tubulin folding pathway.
REACT_22365. Recycling pathway of L1.
REACT_25201. Kinesins.
REACT_268024. Intraflagellar transport.
REACT_268265. Assembly of the primary cilium.
REACT_268323. Hedgehog 'off' state.
REACT_355252. RHO GTPases Activate Formins.
REACT_355469. RHO GTPases activate IQGAPs.
REACT_682. Mitotic Prometaphase.
REACT_9509. Gap junction assembly.

Miscellaneous databases

ChiTaRSiTUBA1B. human.
EvolutionaryTraceiP68363.
GeneWikiiTUBA1B.
GenomeRNAii10376.
NextBioi39315.
PROiP68363.
SOURCEiSearch...

Gene expression databases

BgeeiP68363.
CleanExiHS_TUBA1B.
ExpressionAtlasiP68363. baseline and differential.
GenevestigatoriP68363.

Family and domain databases

Gene3Di1.10.287.600. 1 hit.
3.30.1330.20. 1 hit.
3.40.50.1440. 1 hit.
InterProiIPR002452. Alpha_tubulin.
IPR008280. Tub_FtsZ_C.
IPR000217. Tubulin.
IPR018316. Tubulin/FtsZ_2-layer-sand-dom.
IPR023123. Tubulin_C.
IPR017975. Tubulin_CS.
IPR003008. Tubulin_FtsZ_GTPase.
[Graphical view]
PANTHERiPTHR11588. PTHR11588. 1 hit.
PfamiPF00091. Tubulin. 1 hit.
PF03953. Tubulin_C. 1 hit.
[Graphical view]
PRINTSiPR01162. ALPHATUBULIN.
PR01161. TUBULIN.
SMARTiSM00864. Tubulin. 1 hit.
SM00865. Tubulin_C. 1 hit.
[Graphical view]
SUPFAMiSSF52490. SSF52490. 1 hit.
SSF55307. SSF55307. 1 hit.
PROSITEiPS00227. TUBULIN. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Expression of human alpha-tubulin genes: interspecies conservation of 3' untranslated regions."
    Cowan N.J., Dobner P., Fuchs E.V., Cleveland D.W.
    Mol. Cell. Biol. 3:1738-1745(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Tissue: Keratinocyte.
  2. de Hostos E.L.
    Submitted (JUL-1998) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  3. "Gene response of gangliocytes stimulated by Herpes simplex virus type 1."
    Li Q., Liu L., Ma S.
    Submitted (FEB-2006) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  4. "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 2).
    Tissue: Brain, Colon, Eye, Kidney, Lung, Muscle, Placenta, Prostate, Skin and Uterus.
  5. Lubec G., Afjehi-Sadat L., Vishwanath V., Chen W.-Q., Sun Y.
    Submitted (DEC-2008) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 41-60; 65-79; 113-121; 230-280; 312-320; 327-336; 340-370; 374-390; 395-401 AND 403-422, IDENTIFICATION BY MASS SPECTROMETRY.
    Tissue: Brain, Cajal-Retzius cell and Fetal brain cortex.
  6. Bienvenut W.V., Waridel P., Quadroni M.
    Submitted (MAR-2009) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 41-79; 65-79; 85-121; 125-164; 216-304; 312-370 AND 374-451, PHOSPHORYLATION AT SER-48 AND SER-232, METHYLATION AT ARG-339, IDENTIFICATION BY MASS SPECTROMETRY.
    Tissue: Embryonic kidney.
  7. "C-terminal fragments of alpha- and beta-tubulin form amyloid fibrils in vitro and associate with amyloid deposits of familial cerebral amyloid angiopathy, British type."
    Baumann M.H., Wisniewski T., Levy E., Plant G.T., Ghiso J.
    Biochem. Biophys. Res. Commun. 219:238-242(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 353-370 AND 395-401.
    Tissue: Brain.
  8. "Evolutionary divergence of enzymatic mechanisms for posttranslational polyglycylation."
    Rogowski K., Juge F., van Dijk J., Wloga D., Strub J.-M., Levilliers N., Thomas D., Bre M.-H., Van Dorsselaer A., Gaertig J., Janke C.
    Cell 137:1076-1087(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: GLYCYLATION.
  9. "Structural basis for tubulin recognition by cytoplasmic linker protein 170 and its autoinhibition."
    Mishima M., Maesaki R., Kasa M., Watanabe T., Fukata M., Kaibuchi K., Hakoshima T.
    Proc. Natl. Acad. Sci. U.S.A. 104:10346-10351(2007) [PubMed] [Europe PMC] [Abstract]
    Cited for: STRUCTURE BY NMR OF 416-451 IN COMPLEX WITH CLIP1.

Entry informationi

Entry nameiTBA1B_HUMAN
AccessioniPrimary (citable) accession number: P68363
Secondary accession number(s): P04687
, P05209, Q27I68, Q8WU19
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 13, 1987
Last sequence update: August 13, 1987
Last modified: May 27, 2015
This is version 123 of the entry and version 1 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 12
    Human chromosome 12: 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

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.