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Protein

Sulfhydryl oxidase 2

Gene

QSOX2

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

Functioni

Catalyzes the oxidation of sulfhydryl groups in peptide and protein thiols to disulfides with the reduction of oxygen to hydrogen peroxide. May contribute to disulfide bond formation in a variety of secreted proteins. Also seems to play a role in regulating the sensitization of neuroblastoma cells for interferon-gamma-induced apoptosis.1 Publication

Catalytic activityi

2 R'C(R)SH + O2 = R'C(R)S-S(R)CR' + H2O2.

Cofactori

FADCuratedNote: Binds 1 FAD per subunit.Curated

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Active sitei91 – 911NucleophileBy similarity
Active sitei94 – 941NucleophileBy similarity
Binding sitei426 – 4261FADBy similarity
Binding sitei433 – 4331FADBy similarity
Binding sitei437 – 4371FADBy similarity
Binding sitei478 – 4781FADBy similarity
Binding sitei482 – 4821FADBy similarity
Binding sitei527 – 5271FADBy similarity
Binding sitei530 – 5301FADBy similarity

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi505 – 5128FADBy similarity

GO - Molecular functioni

  1. thiol oxidase activity Source: UniProtKB-EC

GO - Biological processi

  1. cell redox homeostasis Source: InterPro
Complete GO annotation...

Keywords - Molecular functioni

Oxidoreductase

Keywords - Ligandi

FAD, Flavoprotein

Enzyme and pathway databases

BRENDAi1.8.3.2. 2681.

Names & Taxonomyi

Protein namesi
Recommended name:
Sulfhydryl oxidase 2 (EC:1.8.3.2)
Alternative name(s):
Neuroblastoma-derived sulfhydryl oxidase
Quiescin Q6-like protein 1
Gene namesi
Name:QSOX2
Synonyms:QSCN6L1, SOXN
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 9

Organism-specific databases

HGNCiHGNC:30249. QSOX2.

Subcellular locationi

  1. Membrane 1 Publication; Single-pass membrane protein 1 Publication
  2. Secreted 1 Publication
  3. Cell membrane Curated; Single-pass membrane protein Curated
  4. Nucleus membrane Curated; Single-pass membrane protein Curated

  5. Note: Seems to be predominantly targeted to the nuclear and outer plasma membrane.

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Transmembranei662 – 68221HelicalSequence AnalysisAdd
BLAST

GO - Cellular componenti

  1. extracellular region Source: UniProtKB-SubCell
  2. integral component of membrane Source: UniProtKB-KW
  3. nuclear membrane Source: UniProtKB-SubCell
  4. plasma membrane Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Membrane, Nucleus, Secreted

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA162400588.

Polymorphism and mutation databases

BioMutaiQSOX2.
DMDMi158958335.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Signal peptidei1 – 2121Sequence AnalysisAdd
BLAST
Chaini22 – 698677Sulfhydryl oxidase 2PRO_0000249538Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Glycosylationi77 – 771N-linked (GlcNAc...)Sequence Analysis
Disulfide bondi91 ↔ 94Redox-activePROSITE-ProRule annotation
Glycosylationi178 – 1781N-linked (GlcNAc...)Sequence Analysis
Glycosylationi218 – 2181N-linked (GlcNAc...)Sequence Analysis
Glycosylationi266 – 2661N-linked (GlcNAc...)Sequence Analysis
Disulfide bondi418 ↔ 430PROSITE-ProRule annotation
Disulfide bondi476 ↔ 479PROSITE-ProRule annotation
Disulfide bondi536 ↔ 539PROSITE-ProRule annotation
Modified residuei579 – 5791Phosphoserine1 Publication

Keywords - PTMi

Disulfide bond, Glycoprotein, Phosphoprotein

Proteomic databases

MaxQBiQ6ZRP7.
PaxDbiQ6ZRP7.
PRIDEiQ6ZRP7.

PTM databases

PhosphoSiteiQ6ZRP7.

Expressioni

Tissue specificityi

Expressed in pancreas, brain, placenta, kidney, heart and fetal tissues. Weakly expressed in lung, liver and skeletal muscles.1 Publication

Gene expression databases

BgeeiQ6ZRP7.
CleanExiHS_QSOX2.
GenevestigatoriQ6ZRP7.

Organism-specific databases

HPAiHPA012716.

Interactioni

Protein-protein interaction databases

BioGridi127987. 10 interactions.
STRINGi9606.ENSP00000351536.

Structurei

3D structure databases

ProteinModelPortaliQ6ZRP7.
SMRiQ6ZRP7. Positions 58-568.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini34 – 178145ThioredoxinPROSITE-ProRule annotationAdd
BLAST
Domaini421 – 530110ERV/ALR sulfhydryl oxidasePROSITE-ProRule annotationAdd
BLAST

Compositional bias

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Compositional biasi41 – 444Poly-Ala
Compositional biasi588 – 5914Poly-Glu

Sequence similaritiesi

Contains 1 ERV/ALR sulfhydryl oxidase domain.PROSITE-ProRule annotation
Contains 1 thioredoxin domain.PROSITE-ProRule annotation

Keywords - Domaini

Signal, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG237986.
GeneTreeiENSGT00390000008045.
HOVERGENiHBG080360.
InParanoidiQ6ZRP7.
KOiK10758.
OMAiDPIQPSD.
PhylomeDBiQ6ZRP7.
TreeFamiTF316749.

Family and domain databases

Gene3Di1.20.120.310. 1 hit.
3.40.30.10. 1 hit.
InterProiIPR017905. ERV/ALR_sulphydryl_oxidase.
IPR012336. Thioredoxin-like_fold.
IPR013766. Thioredoxin_domain.
[Graphical view]
PfamiPF04777. Evr1_Alr. 1 hit.
PF00085. Thioredoxin. 1 hit.
[Graphical view]
SUPFAMiSSF52833. SSF52833. 1 hit.
SSF69000. SSF69000. 1 hit.
PROSITEiPS51324. ERV_ALR. 1 hit.
PS51352. THIOREDOXIN_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

Q6ZRP7-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MAAAGAAVAR SPGIGAGPAL RARRSPPPRA ARLPRLLVLL AAAAVGPGAG
60 70 80 90 100
GAARLYRAGE DAVWVLDSGS VRGATANSSA AWLVQFYSSW CGHCIGYAPT
110 120 130 140 150
WRALAGDVRD WASAIRVAAL DCMEEKNQAV CHDYDIHFYP TFRYFKAFTK
160 170 180 190 200
EFTTGENFKG PDRELRTVRQ TMIDFLQNHT EGSRPPACPR LDPIQPSDVL
210 220 230 240 250
SLLDNRGSHY VAIVFESNSS YLGREVILDL IPYESIVVTR ALDGDKAFLE
260 270 280 290 300
KLGVSSVPSC YLIYPNGSHG LINVVKPLRA FFSSYLKSLP DVRKKSLPLP
310 320 330 340 350
EKPHKEENSE IVVWREFDKS KLYTVDLESG LHYLLRVELA AHKSLAGAEL
360 370 380 390 400
KTLKDFVTVL AKLFPGRPPV KKLLEMLQEW LASLPLDRIP YNAVLDLVNN
410 420 430 440 450
KMRISGIFLT NHIKWVGCQG SRSELRGYPC SLWKLFHTLT VEASTHPDAL
460 470 480 490 500
VGTGFEDDPQ AVLQTMRRYV HTFFGCKECG EHFEEMAKES MDSVKTPDQA
510 520 530 540 550
ILWLWKKHNM VNGRLAGHLS EDPRFPKLQW PTPDLCPACH EEIKGLASWD
560 570 580 590 600
EGHVLTFLKQ HYGRDNLLDT YSADQGDSSE GGTLARGEEE EKRLTPPEVS
610 620 630 640 650
HGDRDTQSVR PPGALGPRPA LPESLHHSLD GKLQSLDGPG AHKEVGGAAP
660 670 680 690
FLGVDFSSLD MSLCVVLYVA SSLFLMVMYF FFRVRSRRWK VKHHHPAV
Length:698
Mass (Da):77,529
Last modified:July 24, 2007 - v3
Checksum:i7F2B3F890AE657CF
GO

Sequence cautioni

The sequence BAC87262.1 differs from that shown. Reason: Erroneous initiation. Curated
The sequence CAC85331.1 differs from that shown. Reason: Frameshift at positions 354, 369, 616 and 618. Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti96 – 961G → A in CAC85331 (PubMed:14633699).Curated
Sequence conflicti205 – 2051N → K in BAC87262 (PubMed:14702039).Curated
Sequence conflicti224 – 2241R → W in CAC85331 (PubMed:14633699).Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti126 – 1261K → E.
Corresponds to variant rs12380852 [ dbSNP | Ensembl ].
VAR_027435

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AJ318051 mRNA. Translation: CAC85331.1. Frameshift.
AL138781, CR392000 Genomic DNA. Translation: CAI16881.2.
CR392000, AL138781 Genomic DNA. Translation: CAM28352.1.
AK128077 mRNA. Translation: BAC87262.1. Different initiation.
AL834369 mRNA. Translation: CAD39032.1.
CCDSiCCDS35178.1.
RefSeqiNP_859052.3. NM_181701.3.
UniGeneiHs.144073.

Genome annotation databases

EnsembliENST00000358701; ENSP00000351536; ENSG00000165661.
GeneIDi169714.
KEGGihsa:169714.
UCSCiuc010nbi.2. human.

Polymorphism and mutation databases

BioMutaiQSOX2.

Keywords - Coding sequence diversityi

Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AJ318051 mRNA. Translation: CAC85331.1. Frameshift.
AL138781, CR392000 Genomic DNA. Translation: CAI16881.2.
CR392000, AL138781 Genomic DNA. Translation: CAM28352.1.
AK128077 mRNA. Translation: BAC87262.1. Different initiation.
AL834369 mRNA. Translation: CAD39032.1.
CCDSiCCDS35178.1.
RefSeqiNP_859052.3. NM_181701.3.
UniGeneiHs.144073.

3D structure databases

ProteinModelPortaliQ6ZRP7.
SMRiQ6ZRP7. Positions 58-568.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi127987. 10 interactions.
STRINGi9606.ENSP00000351536.

PTM databases

PhosphoSiteiQ6ZRP7.

Polymorphism and mutation databases

BioMutaiQSOX2.
DMDMi158958335.

Proteomic databases

MaxQBiQ6ZRP7.
PaxDbiQ6ZRP7.
PRIDEiQ6ZRP7.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000358701; ENSP00000351536; ENSG00000165661.
GeneIDi169714.
KEGGihsa:169714.
UCSCiuc010nbi.2. human.

Organism-specific databases

CTDi169714.
GeneCardsiGC09M139098.
H-InvDBHIX0008541.
HGNCiHGNC:30249. QSOX2.
HPAiHPA012716.
MIMi612860. gene.
neXtProtiNX_Q6ZRP7.
PharmGKBiPA162400588.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG237986.
GeneTreeiENSGT00390000008045.
HOVERGENiHBG080360.
InParanoidiQ6ZRP7.
KOiK10758.
OMAiDPIQPSD.
PhylomeDBiQ6ZRP7.
TreeFamiTF316749.

Enzyme and pathway databases

BRENDAi1.8.3.2. 2681.

Miscellaneous databases

ChiTaRSiQSOX2. human.
GenomeRNAii169714.
NextBioi88829.
PROiQ6ZRP7.
SOURCEiSearch...

Gene expression databases

BgeeiQ6ZRP7.
CleanExiHS_QSOX2.
GenevestigatoriQ6ZRP7.

Family and domain databases

Gene3Di1.20.120.310. 1 hit.
3.40.30.10. 1 hit.
InterProiIPR017905. ERV/ALR_sulphydryl_oxidase.
IPR012336. Thioredoxin-like_fold.
IPR013766. Thioredoxin_domain.
[Graphical view]
PfamiPF04777. Evr1_Alr. 1 hit.
PF00085. Thioredoxin. 1 hit.
[Graphical view]
SUPFAMiSSF52833. SSF52833. 1 hit.
SSF69000. SSF69000. 1 hit.
PROSITEiPS51324. ERV_ALR. 1 hit.
PS51352. THIOREDOXIN_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Neuroblastoma-derived sulfhydryl oxidase, a new member of the sulfhydryl oxidase/quiescin 6 family, regulates sensitization to interferon gamma-induced cell death in human neuroblastoma cells."
    Wittke I., Wiedemeyer R., Pillmann A., Savelyeva L., Westermann F., Schwab M.
    Cancer Res. 63:7742-7752(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
  2. "DNA sequence and analysis of human chromosome 9."
    Humphray S.J., Oliver K., Hunt A.R., Plumb R.W., Loveland J.E., Howe K.L., Andrews T.D., Searle S., Hunt S.E., Scott C.E., Jones M.C., Ainscough R., Almeida J.P., Ambrose K.D., Ashwell R.I.S., Babbage A.K., Babbage S., Bagguley C.L.
    , Bailey J., Banerjee R., Barker D.J., Barlow K.F., Bates K., Beasley H., Beasley O., Bird C.P., Bray-Allen S., Brown A.J., Brown J.Y., Burford D., Burrill W., Burton J., Carder C., Carter N.P., Chapman J.C., Chen Y., Clarke G., Clark S.Y., Clee C.M., Clegg S., Collier R.E., Corby N., Crosier M., Cummings A.T., Davies J., Dhami P., Dunn M., Dutta I., Dyer L.W., Earthrowl M.E., Faulkner L., Fleming C.J., Frankish A., Frankland J.A., French L., Fricker D.G., Garner P., Garnett J., Ghori J., Gilbert J.G.R., Glison C., Grafham D.V., Gribble S., Griffiths C., Griffiths-Jones S., Grocock R., Guy J., Hall R.E., Hammond S., Harley J.L., Harrison E.S.I., Hart E.A., Heath P.D., Henderson C.D., Hopkins B.L., Howard P.J., Howden P.J., Huckle E., Johnson C., Johnson D., Joy A.A., Kay M., Keenan S., Kershaw J.K., Kimberley A.M., King A., Knights A., Laird G.K., Langford C., Lawlor S., Leongamornlert D.A., Leversha M., Lloyd C., Lloyd D.M., Lovell J., Martin S., Mashreghi-Mohammadi M., Matthews L., McLaren S., McLay K.E., McMurray A., Milne S., Nickerson T., Nisbett J., Nordsiek G., Pearce A.V., Peck A.I., Porter K.M., Pandian R., Pelan S., Phillimore B., Povey S., Ramsey Y., Rand V., Scharfe M., Sehra H.K., Shownkeen R., Sims S.K., Skuce C.D., Smith M., Steward C.A., Swarbreck D., Sycamore N., Tester J., Thorpe A., Tracey A., Tromans A., Thomas D.W., Wall M., Wallis J.M., West A.P., Whitehead S.L., Willey D.L., Williams S.A., Wilming L., Wray P.W., Young L., Ashurst J.L., Coulson A., Blocker H., Durbin R.M., Sulston J.E., Hubbard T., Jackson M.J., Bentley D.R., Beck S., Rogers J., Dunham I.
    Nature 429:369-374(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  3. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 100-698.
    Tissue: Testis.
  4. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 158-698.
    Tissue: Melanoma.
  5. "Kinase-selective enrichment enables quantitative phosphoproteomics of the kinome across the cell cycle."
    Daub H., Olsen J.V., Bairlein M., Gnad F., Oppermann F.S., Korner R., Greff Z., Keri G., Stemmann O., Mann M.
    Mol. Cell 31:438-448(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  6. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  7. "Quantitative phosphoproteomics reveals widespread full phosphorylation site occupancy during mitosis."
    Olsen J.V., Vermeulen M., Santamaria A., Kumar C., Miller M.L., Jensen L.J., Gnad F., Cox J., Jensen T.S., Nigg E.A., Brunak S., Mann M.
    Sci. Signal. 3:RA3-RA3(2010) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  8. "System-wide temporal characterization of the proteome and phosphoproteome of human embryonic stem cell differentiation."
    Rigbolt K.T., Prokhorova T.A., Akimov V., Henningsen J., Johansen P.T., Kratchmarova I., Kassem M., Mann M., Olsen J.V., Blagoev B.
    Sci. Signal. 4:RS3-RS3(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-579, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  9. "An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
    Bian Y., Song C., Cheng K., Dong M., Wang F., Huang J., Sun D., Wang L., Ye M., Zou H.
    J. Proteomics 96:253-262(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Liver.

Entry informationi

Entry nameiQSOX2_HUMAN
AccessioniPrimary (citable) accession number: Q6ZRP7
Secondary accession number(s): A2CEE0
, A6NLB0, Q5TB37, Q7Z7B6, Q86VV7, Q8N3G2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: September 19, 2006
Last sequence update: July 24, 2007
Last modified: April 29, 2015
This is version 106 of the entry and version 3 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

Complete proteome, Reference proteome

Documents

  1. Human chromosome 9
    Human chromosome 9: 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. 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.