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Protein

Ubiquilin-1

Gene

Ubqln1

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

Functioni

Plays an important role in the regulation of different protein degradation mechanisms and pathways including ubiquitin-proteasome system (UPS), autophagy and endoplasmic reticulum-associated protein degradation (ERAD) pathway. Mediates the proteasomal targeting of misfolded or accumulated proteins for degradation by binding (via UBA domain) to their polyubiquitin chains and by interacting (via ubiquitin-like domain) with the subunits of the proteasome. Plays a role in the ERAD pathway via its interaction with ER-localized proteins UBXN4, VCP and HERPUD1 and may form a link between the polyubiquitinated ERAD substrates and the proteasome. Plays a role in unfolded protein response (UPR) by attenuating the induction of UPR-inducible genes, DDTI3/CHOP, HSPA5 and PDIA2 during ER stress. Involved in the regulation of macroautophagy and autophagosome formation; required for maturation of autophagy-related protein LC3 from the cytosolic form LC3-I to the membrane-bound form LC3-II and may assist in the maturation of autophagosomes to autolysosomes by mediating autophagosome-lysosome fusion. Negatively regulates the TICAM1/TRIF-dependent toll-like receptor signaling pathway by decreasing the abundance of TICAM1 via the autophagic pathway. Plays a key role in the regulation of the levels of PSEN1 by targeting its accumulation to aggresomes which may then be removed from cells by autophagocytosis. Promotes the ubiquitination and lysosomal degradation of ORAI1, consequently downregulating the ORAI1-mediated Ca2+ mobilization. Suppresses the maturation and proteasomal degradation of amyloid beta A4 protein (A4) by stimulating the lysine 63 (K63)-linked polyubiquitination. Delays the maturation of A4 by sequestering it in the Golgi apparatus and preventing its transport to the cell surface for subsequent processing (By similarity). Links CD47 to the cytoskeleton (PubMed:10549293).By similarity1 Publication

GO - Molecular functioni

  • identical protein binding Source: MGI
  • intermediate filament binding Source: UniProtKB
  • kinase binding Source: UniProtKB
  • polyubiquitin binding Source: UniProtKB
  • receptor binding Source: UniProtKB

GO - Biological processi

Complete GO annotation...

Keywords - Biological processi

Autophagy

Names & Taxonomyi

Protein namesi
Recommended name:
Ubiquilin-1
Alternative name(s):
Protein linking IAP with cytoskeleton 1
Short name:
PLIC-1
Gene namesi
Name:Ubqln1
Synonyms:Plic1
OrganismiMus musculus (Mouse)
Taxonomic identifieri10090 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeMusMus
Proteomesi
  • UP000000589 Componenti: Chromosome 13

Organism-specific databases

MGIiMGI:1860276. Ubqln1.

Subcellular locationi

  • Nucleus By similarity
  • Cytoplasm 1 Publication
  • Endoplasmic reticulum By similarity
  • Cytoplasmic vesicleautophagosome 1 Publication
  • Cell membrane By similarity

  • Note: Detected in neuronal processes and at synapses. Recruited to the ER during ER-associated protein degradation (ERAD). Colocalizes with PSEN1 in the cell membrane and in cytoplasmic juxtanuclear structures called aggresomes. Colocalizes with ORAI1 and TICAM1 in the autophagosome. Colocalizes with EPS15 and HGS in ubiquitin-rich cytoplasmic aggregates that are not endocytic compartments and with EPS15 also in aggresomes.By similarity

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Cytoplasm, Cytoplasmic vesicle, Endoplasmic reticulum, Membrane, Nucleus, Proteasome

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methionineiRemovedBy similarity
Chaini2 – 582581Ubiquilin-1PRO_0000211009Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei2 – 21N-acetylalanineBy similarity

Post-translational modificationi

Degraded during both macroautophagy and during chaperone-mediated autophagy (CMA).By similarity
Phosphorylated.By similarity
Ubiquitinated.By similarity

Keywords - PTMi

Acetylation, Ubl conjugation

Proteomic databases

EPDiQ8R317.
MaxQBiQ8R317.
PaxDbiQ8R317.
PeptideAtlasiQ8R317.
PRIDEiQ8R317.

2D gel databases

REPRODUCTION-2DPAGEQ8R317.

PTM databases

iPTMnetiQ8R317.
PhosphoSiteiQ8R317.

Expressioni

Tissue specificityi

Highly expressed in heart, brain, liver, smooth muscle and kidney.1 Publication

Gene expression databases

BgeeiQ8R317.
CleanExiMM_UBQLN1.
GenevisibleiQ8R317. MM.

Interactioni

Subunit structurei

Monomer and homodimer. Heterodimer with UBQLN2 (By similarity). Binds CD47 (PubMed:10549293). Binds NBL1, GABRA1, GABRA2, GABRA3, GABRA6, GABRB1, GABRB2 and GABRB3. Binds UBE3A, BTRC, P4HB and MTOR. Interacts with the proteasome 19S subunit. Interacts (via ubiquitin-like domain) with TREX1; the interaction is direct and may control TREX1 subcellular location. Forms a complex with UBXN4 and VCP. Interacts (via UBA domain) with UBQLN4 (via ubiquitin-like domain). Found in a complex with UBQLN2 and MAP1LC3A/B/C. The monomeric form interacts with PSEN1 and PSEN2. Interacts with ORAI1. Interacts (via UBA domain) with TICAM1. Interacts with EPS15. Interacts (via UBA domain) with UBA52 and (via ubiquitin-like domain) with PSMD3 and PSMD4. Interacts with HERPUD1. Interacts with MAP1LC3A/B/C in the presence of UBQLN4. Interacts (via ubiquitin-like domain) with EPS15 (via UIM domains) and both the ubiquitinated and non-ubiquitinated forms can interact with EPS15. Interacts (via ubiquitin-like domain) with EPS15L1, HGS (via UIM domain) and STAM2 (via UIM domain) (By similarity).By similarity1 Publication

GO - Molecular functioni

  • identical protein binding Source: MGI
  • intermediate filament binding Source: UniProtKB
  • kinase binding Source: UniProtKB
  • polyubiquitin binding Source: UniProtKB
  • receptor binding Source: UniProtKB

Protein-protein interaction databases

BioGridi207807. 5 interactions.
IntActiQ8R317. 4 interactions.
MINTiMINT-4139320.
STRINGi10090.ENSMUSP00000050191.

Structurei

3D structure databases

ProteinModelPortaliQ8R317.
SMRiQ8R317. Positions 24-131, 530-579.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini28 – 10275Ubiquitin-likePROSITE-ProRule annotationAdd
BLAST
Domaini173 – 20129STI1 1Sequence analysisAdd
BLAST
Domaini203 – 24240STI1 2Sequence analysisAdd
BLAST
Domaini381 – 42848STI1 3Sequence analysisAdd
BLAST
Domaini432 – 46433STI1 4Sequence analysisAdd
BLAST
Domaini539 – 57941UBAPROSITE-ProRule annotationAdd
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni169 – 422254Interaction with UBXN4By similarityAdd
BLAST

Compositional bias

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Compositional biasi372 – 546175Gln-richAdd
BLAST

Domaini

The UBA domain mediates binding to PSEN1 and PSEN2. It also binds ubiquitin with micromolar affinity, independently of polyubiquitin linkage type. Essential for its association with microtubule-associated protein 1 light chain 3 (MAP1LC3).By similarity
The ubiquitin-like domain mediates its association with the subunits of the proteasome.By similarity
Dimerization is dependent upon the central region of the protein containing the STI1 domains and is independent of its ubiquitin-like and UBA domains.By similarity

Sequence similaritiesi

Contains 4 STI1 domains.Sequence analysis
Contains 1 UBA domain.PROSITE-ProRule annotation
Contains 1 ubiquitin-like domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiKOG0010. Eukaryota.
COG5272. LUCA.
GeneTreeiENSGT00390000005720.
HOVERGENiHBG064537.
InParanoidiQ8R317.
KOiK04523.
OMAiQNCDISA.
OrthoDBiEOG7HF1J8.
PhylomeDBiQ8R317.
TreeFamiTF314412.

Family and domain databases

InterProiIPR006636. STI1_HS-bd.
IPR015940. UBA.
IPR009060. UBA-like.
IPR015496. Ubiquilin.
IPR028430. Ubiquilin-1/2.
IPR029071. Ubiquitin-rel_dom.
IPR000626. Ubiquitin_dom.
[Graphical view]
PANTHERiPTHR10677. PTHR10677. 1 hit.
PTHR10677:SF5. PTHR10677:SF5. 1 hit.
PfamiPF00627. UBA. 1 hit.
PF00240. ubiquitin. 1 hit.
[Graphical view]
SMARTiSM00727. STI1. 4 hits.
SM00165. UBA. 1 hit.
SM00213. UBQ. 1 hit.
[Graphical view]
SUPFAMiSSF46934. SSF46934. 1 hit.
SSF54236. SSF54236. 1 hit.
PROSITEiPS50030. UBA. 1 hit.
PS50053. UBIQUITIN_2. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

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

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

Isoform 1 (identifier: Q8R317-1) [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
MAESAESGGP PGAQDSAADG GPAEPKIMKV TVKTPKEKEE FAVPENSSVQ
60 70 80 90 100
QFKEEISKRF KSHIDQLVLI FAGKILKDQD TLSQHGIHDG LTVHLVIKTQ
110 120 130 140 150
NRPQDNSAQQ TNAPGSTVTS SPAPDSNPTS GSAANSSFGV GGLGGLAGLS
160 170 180 190 200
SLGLNTTNFS ELQSQMQRQL LSNPEMMVQI MENPFVQSML SNPDLMRQLI
210 220 230 240 250
MANPQMQQLI QRNPEISHML NNPDIMRQTL ELARNPAMMQ EMMRNQDRAL
260 270 280 290 300
SNLESIPGGY NALRRMYTDI QEPMLNAAQE QFGGNPFASL VSSSSSAEGT
310 320 330 340 350
QPSRTENRDP LPNPWAPQTS QSSPASGTTG STTNTMSTSG GTATSTPAGQ
360 370 380 390 400
STSGPSLVPG AGASMFNTPG MQSLLQQITE NPQLMQNMLS APYMRSMLQS
410 420 430 440 450
LSQNPDLAAQ MMLNNPLFAG NPQLQEQMRQ QLPTFLQQMQ NPDTLSAMSN
460 470 480 490 500
PRAMQALLQI QQGLQTLATE APGLIPGFTP GLAAGNSGGS SGTNAPSTAP
510 520 530 540 550
SEDTNPQGGT AEPGHQQFIQ QMLQALAGVN PQLQSPEVRF QQQLEQLSAM
560 570 580
GFLNREANLQ ALIATGGDIN AAIERLLGSQ PS
Length:582
Mass (Da):61,976
Last modified:June 1, 2002 - v1
Checksum:iDF0CF98794CC3A04
GO
Isoform 2 (identifier: Q8R317-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     410-437: Missing.

Show »
Length:554
Mass (Da):58,678
Checksum:iF9255C9985A4C029
GO

Sequence cautioni

The sequence AAF01365.1 differs from that shown.Several sequencing errors.Curated
The sequence AAH51098.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.Curated
The sequence BAC33666.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti175 – 1751E → G in BAC33365 (PubMed:16141072).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei410 – 43728Missing in isoform 2. 2 PublicationsVSP_009788Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF177345 mRNA. Translation: AAF01365.1. Sequence problems.
AK048534 mRNA. Translation: BAC33365.1.
AK049298 mRNA. Translation: BAC33666.1. Different initiation.
AK004183 mRNA. Translation: BAB23211.1.
BC010213 mRNA. Translation: AAH10213.1.
BC026847 mRNA. Translation: AAH26847.1.
BC027375 mRNA. Translation: AAH27375.1.
BC028857 mRNA. Translation: AAH28857.1.
BC051098 mRNA. Translation: AAH51098.1. Different initiation.
CCDSiCCDS26569.1. [Q8R317-2]
CCDS49281.1. [Q8R317-1]
RefSeqiNP_081118.4. NM_026842.4. [Q8R317-1]
NP_689420.1. NM_152234.2. [Q8R317-2]
UniGeneiMm.182053.

Genome annotation databases

EnsembliENSMUST00000058735; ENSMUSP00000050191; ENSMUSG00000005312. [Q8R317-1]
ENSMUST00000076454; ENSMUSP00000075782; ENSMUSG00000005312. [Q8R317-2]
GeneIDi56085.
KEGGimmu:56085.
UCSCiuc007qtl.2. mouse. [Q8R317-2]
uc007qtm.2. mouse. [Q8R317-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF177345 mRNA. Translation: AAF01365.1. Sequence problems.
AK048534 mRNA. Translation: BAC33365.1.
AK049298 mRNA. Translation: BAC33666.1. Different initiation.
AK004183 mRNA. Translation: BAB23211.1.
BC010213 mRNA. Translation: AAH10213.1.
BC026847 mRNA. Translation: AAH26847.1.
BC027375 mRNA. Translation: AAH27375.1.
BC028857 mRNA. Translation: AAH28857.1.
BC051098 mRNA. Translation: AAH51098.1. Different initiation.
CCDSiCCDS26569.1. [Q8R317-2]
CCDS49281.1. [Q8R317-1]
RefSeqiNP_081118.4. NM_026842.4. [Q8R317-1]
NP_689420.1. NM_152234.2. [Q8R317-2]
UniGeneiMm.182053.

3D structure databases

ProteinModelPortaliQ8R317.
SMRiQ8R317. Positions 24-131, 530-579.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi207807. 5 interactions.
IntActiQ8R317. 4 interactions.
MINTiMINT-4139320.
STRINGi10090.ENSMUSP00000050191.

PTM databases

iPTMnetiQ8R317.
PhosphoSiteiQ8R317.

2D gel databases

REPRODUCTION-2DPAGEQ8R317.

Proteomic databases

EPDiQ8R317.
MaxQBiQ8R317.
PaxDbiQ8R317.
PeptideAtlasiQ8R317.
PRIDEiQ8R317.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSMUST00000058735; ENSMUSP00000050191; ENSMUSG00000005312. [Q8R317-1]
ENSMUST00000076454; ENSMUSP00000075782; ENSMUSG00000005312. [Q8R317-2]
GeneIDi56085.
KEGGimmu:56085.
UCSCiuc007qtl.2. mouse. [Q8R317-2]
uc007qtm.2. mouse. [Q8R317-1]

Organism-specific databases

CTDi29979.
MGIiMGI:1860276. Ubqln1.

Phylogenomic databases

eggNOGiKOG0010. Eukaryota.
COG5272. LUCA.
GeneTreeiENSGT00390000005720.
HOVERGENiHBG064537.
InParanoidiQ8R317.
KOiK04523.
OMAiQNCDISA.
OrthoDBiEOG7HF1J8.
PhylomeDBiQ8R317.
TreeFamiTF314412.

Miscellaneous databases

ChiTaRSiUbqln1. mouse.
PROiQ8R317.
SOURCEiSearch...

Gene expression databases

BgeeiQ8R317.
CleanExiMM_UBQLN1.
GenevisibleiQ8R317. MM.

Family and domain databases

InterProiIPR006636. STI1_HS-bd.
IPR015940. UBA.
IPR009060. UBA-like.
IPR015496. Ubiquilin.
IPR028430. Ubiquilin-1/2.
IPR029071. Ubiquitin-rel_dom.
IPR000626. Ubiquitin_dom.
[Graphical view]
PANTHERiPTHR10677. PTHR10677. 1 hit.
PTHR10677:SF5. PTHR10677:SF5. 1 hit.
PfamiPF00627. UBA. 1 hit.
PF00240. ubiquitin. 1 hit.
[Graphical view]
SMARTiSM00727. STI1. 4 hits.
SM00165. UBA. 1 hit.
SM00213. UBQ. 1 hit.
[Graphical view]
SUPFAMiSSF46934. SSF46934. 1 hit.
SSF54236. SSF54236. 1 hit.
PROSITEiPS50030. UBA. 1 hit.
PS50053. UBIQUITIN_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Ubiquitin-related proteins regulate interaction of vimentin intermediate filaments with the plasma membrane."
    Wu A.-L., Wang J., Zheleznyak A., Brown E.J.
    Mol. Cell 4:619-625(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, INTERACTION WITH CD47.
    Strain: Swiss Webster / NIH.
    Tissue: Embryo.
  2. "The transcriptional landscape of the mammalian genome."
    Carninci P., Kasukawa T., Katayama S., Gough J., Frith M.C., Maeda N., Oyama R., Ravasi T., Lenhard B., Wells C., Kodzius R., Shimokawa K., Bajic V.B., Brenner S.E., Batalov S., Forrest A.R., Zavolan M., Davis M.J.
    , Wilming L.G., Aidinis V., Allen J.E., Ambesi-Impiombato A., Apweiler R., Aturaliya R.N., Bailey T.L., Bansal M., Baxter L., Beisel K.W., Bersano T., Bono H., Chalk A.M., Chiu K.P., Choudhary V., Christoffels A., Clutterbuck D.R., Crowe M.L., Dalla E., Dalrymple B.P., de Bono B., Della Gatta G., di Bernardo D., Down T., Engstrom P., Fagiolini M., Faulkner G., Fletcher C.F., Fukushima T., Furuno M., Futaki S., Gariboldi M., Georgii-Hemming P., Gingeras T.R., Gojobori T., Green R.E., Gustincich S., Harbers M., Hayashi Y., Hensch T.K., Hirokawa N., Hill D., Huminiecki L., Iacono M., Ikeo K., Iwama A., Ishikawa T., Jakt M., Kanapin A., Katoh M., Kawasawa Y., Kelso J., Kitamura H., Kitano H., Kollias G., Krishnan S.P., Kruger A., Kummerfeld S.K., Kurochkin I.V., Lareau L.F., Lazarevic D., Lipovich L., Liu J., Liuni S., McWilliam S., Madan Babu M., Madera M., Marchionni L., Matsuda H., Matsuzawa S., Miki H., Mignone F., Miyake S., Morris K., Mottagui-Tabar S., Mulder N., Nakano N., Nakauchi H., Ng P., Nilsson R., Nishiguchi S., Nishikawa S., Nori F., Ohara O., Okazaki Y., Orlando V., Pang K.C., Pavan W.J., Pavesi G., Pesole G., Petrovsky N., Piazza S., Reed J., Reid J.F., Ring B.Z., Ringwald M., Rost B., Ruan Y., Salzberg S.L., Sandelin A., Schneider C., Schoenbach C., Sekiguchi K., Semple C.A., Seno S., Sessa L., Sheng Y., Shibata Y., Shimada H., Shimada K., Silva D., Sinclair B., Sperling S., Stupka E., Sugiura K., Sultana R., Takenaka Y., Taki K., Tammoja K., Tan S.L., Tang S., Taylor M.S., Tegner J., Teichmann S.A., Ueda H.R., van Nimwegen E., Verardo R., Wei C.L., Yagi K., Yamanishi H., Zabarovsky E., Zhu S., Zimmer A., Hide W., Bult C., Grimmond S.M., Teasdale R.D., Liu E.T., Brusic V., Quackenbush J., Wahlestedt C., Mattick J.S., Hume D.A., Kai C., Sasaki D., Tomaru Y., Fukuda S., Kanamori-Katayama M., Suzuki M., Aoki J., Arakawa T., Iida J., Imamura K., Itoh M., Kato T., Kawaji H., Kawagashira N., Kawashima T., Kojima M., Kondo S., Konno H., Nakano K., Ninomiya N., Nishio T., Okada M., Plessy C., Shibata K., Shiraki T., Suzuki S., Tagami M., Waki K., Watahiki A., Okamura-Oho Y., Suzuki H., Kawai J., Hayashizaki Y.
    Science 309:1559-1563(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2).
    Strain: C57BL/6J.
    Tissue: Embryo and Head.
  3. "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: Mammary tumor and Retina.
  4. Lubec G., Yang J.W., Zigmond M.
    Submitted (JUL-2007) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 62-74.
    Tissue: Brain.
  5. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Brain, Brown adipose tissue, Heart, Kidney, Liver, Lung, Pancreas, Spleen and Testis.
  6. Cited for: SUBCELLULAR LOCATION.

Entry informationi

Entry nameiUBQL1_MOUSE
AccessioniPrimary (citable) accession number: Q8R317
Secondary accession number(s): Q80V10
, Q8C7T4, Q8C835, Q8K141, Q91VI8, Q9D0Z0, Q9QZM1
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 29, 2004
Last sequence update: June 1, 2002
Last modified: July 6, 2016
This is version 128 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Direct protein sequencing, 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.