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Protein

Prostasin

Gene

PRSS8

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

Functioni

Possesses a trypsin-like cleavage specificity with a preference for poly-basic substrates. Stimulates epithelial sodium channel (ENaC) activity through activating cleavage of the gamma subunits (SCNN1G).2 Publications

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Active sitei85 – 851Charge relay system
Active sitei134 – 1341Charge relay system
Active sitei238 – 2381Charge relay system

GO - Molecular functioni

  1. serine-type endopeptidase activity Source: InterPro
  2. serine-type peptidase activity Source: ProtInc

GO - Biological processi

  1. positive regulation of sodium ion transport Source: Ensembl
Complete GO annotation...

Keywords - Molecular functioni

Hydrolase, Protease, Serine protease

Enzyme and pathway databases

BRENDAi3.4.21.B6. 2681.

Protein family/group databases

MEROPSiS01.159.

Names & Taxonomyi

Protein namesi
Recommended name:
Prostasin (EC:3.4.21.-)
Alternative name(s):
Channel-activating protease 1
Short name:
CAP1
Serine protease 8
Cleaved into the following 2 chains:
Gene namesi
Name:PRSS8
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 16

Organism-specific databases

HGNCiHGNC:9491. PRSS8.

Subcellular locationi

Prostasin light chain : Secretedextracellular space
Note: Found in the seminal fluid. Secreted after cleavage of its C-terminus.
Prostasin heavy chain : Secretedextracellular space
Note: Found in the seminal fluid. Secreted after cleavage of its C-terminus.

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Transmembranei320 – 34021HelicalSequence AnalysisAdd
BLAST

GO - Cellular componenti

  1. extracellular region Source: ProtInc
  2. extracellular space Source: UniProtKB
  3. extracellular vesicular exosome Source: UniProtKB
  4. integral component of membrane Source: UniProtKB-KW
  5. plasma membrane Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Membrane, Secreted

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA33840.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Signal peptidei1 – 2929Sequence AnalysisAdd
BLAST
Propeptidei30 – 323Activation peptidePRO_0000028027
Chaini33 – 343311ProstasinPRO_0000240511Add
BLAST
Chaini33 – 4412Prostasin light chainPRO_0000028028Add
BLAST
Chaini45 – 322278Prostasin heavy chainPRO_0000028029Add
BLAST
Propeptidei323 – 34321PRO_0000028030Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi37 ↔ 154Interchain (between light and heavy chains)PROSITE-ProRule annotation
Disulfide bondi70 ↔ 86PROSITE-ProRule annotation1 Publication
Glycosylationi159 – 1591N-linked (GlcNAc...)Sequence Analysis
Disulfide bondi168 ↔ 244PROSITE-ProRule annotation1 Publication
Disulfide bondi201 ↔ 223PROSITE-ProRule annotation1 Publication
Disulfide bondi234 ↔ 262PROSITE-ProRule annotation1 Publication

Keywords - PTMi

Disulfide bond, Glycoprotein, Zymogen

Proteomic databases

MaxQBiQ16651.
PaxDbiQ16651.
PRIDEiQ16651.

Expressioni

Tissue specificityi

Found in prostate, liver, salivary gland, kidney, lung, pancreas, colon, bronchus and renal proximal tubular cells. In the prostate gland it may be synthesized in epithelial cells, secreted into the ducts, and excreted into the seminal fluid.

Gene expression databases

BgeeiQ16651.
CleanExiHS_PRSS8.
ExpressionAtlasiQ16651. baseline and differential.
GenevestigatoriQ16651.

Organism-specific databases

HPAiHPA030436.

Interactioni

Subunit structurei

Heterodimer of two chains, light and heavy, held by a disulfide bond.1 Publication

Protein-protein interaction databases

IntActiQ16651. 1 interaction.
MINTiMINT-5000236.
STRINGi9606.ENSP00000319730.

Structurei

Secondary structure

1
343
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi59 – 646Combined sources
Beta strandi67 – 748Combined sources
Beta strandi76 – 827Combined sources
Helixi84 – 863Combined sources
Helixi93 – 953Combined sources
Beta strandi96 – 1016Combined sources
Beta strandi113 – 1153Combined sources
Beta strandi117 – 1226Combined sources
Helixi124 – 1285Combined sources
Beta strandi130 – 1323Combined sources
Beta strandi136 – 1427Combined sources
Beta strandi148 – 1503Combined sources
Beta strandi167 – 1748Combined sources
Beta strandi189 – 1968Combined sources
Helixi198 – 2058Combined sources
Turni206 – 2083Combined sources
Turni218 – 2203Combined sources
Beta strandi221 – 2255Combined sources
Beta strandi227 – 2304Combined sources
Turni235 – 2395Combined sources
Beta strandi241 – 2466Combined sources
Beta strandi249 – 2568Combined sources
Beta strandi260 – 2634Combined sources
Beta strandi269 – 2735Combined sources
Helixi274 – 2774Combined sources
Helixi278 – 28811Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
3DFJX-ray1.45A45-289[»]
3DFLX-ray2.00A45-289[»]
3E0NX-ray1.70B45-305[»]
3E0PX-ray1.70B45-305[»]
3E16X-ray1.60B45-305[»]
3E1XX-ray1.70B45-305[»]
3FVFX-ray1.60B45-305[»]
3GYLX-ray1.30B45-305[»]
3GYMX-ray2.80A/B45-305[»]
ProteinModelPortaliQ16651.
SMRiQ16651. Positions 45-289.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ16651.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini45 – 286242Peptidase S1PROSITE-ProRule annotationAdd
BLAST

Sequence similaritiesi

Belongs to the peptidase S1 family.PROSITE-ProRule annotation
Contains 1 peptidase S1 domain.PROSITE-ProRule annotation

Keywords - Domaini

Signal, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiCOG5640.
GeneTreeiENSGT00760000118810.
HOGENOMiHOG000251820.
HOVERGENiHBG013304.
InParanoidiQ16651.
KOiK08664.
OMAiACGARNR.
OrthoDBiEOG75B84T.
PhylomeDBiQ16651.
TreeFamiTF351676.

Family and domain databases

InterProiIPR001254. Peptidase_S1.
IPR018114. Peptidase_S1_AS.
IPR001314. Peptidase_S1A.
IPR009003. Trypsin-like_Pept_dom.
[Graphical view]
PfamiPF00089. Trypsin. 1 hit.
[Graphical view]
PRINTSiPR00722. CHYMOTRYPSIN.
SMARTiSM00020. Tryp_SPc. 1 hit.
[Graphical view]
SUPFAMiSSF50494. SSF50494. 1 hit.
PROSITEiPS50240. TRYPSIN_DOM. 1 hit.
PS00134. TRYPSIN_HIS. 1 hit.
PS00135. TRYPSIN_SER. 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: Q16651-1) [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
MAQKGVLGPG QLGAVAILLY LGLLRSGTGA EGAEAPCGVA PQARITGGSS
60 70 80 90 100
AVAGQWPWQV SITYEGVHVC GGSLVSEQWV LSAAHCFPSE HHKEAYEVKL
110 120 130 140 150
GAHQLDSYSE DAKVSTLKDI IPHPSYLQEG SQGDIALLQL SRPITFSRYI
160 170 180 190 200
RPICLPAANA SFPNGLHCTV TGWGHVAPSV SLLTPKPLQQ LEVPLISRET
210 220 230 240 250
CNCLYNIDAK PEEPHFVQED MVCAGYVEGG KDACQGDSGG PLSCPVEGLW
260 270 280 290 300
YLTGIVSWGD ACGARNRPGV YTLASSYASW IQSKVTELQP RVVPQTQESQ
310 320 330 340
PDSNLCGSHL AFSSAPAQGL LRPILFLPLG LALGLLSPWL SEH
Length:343
Mass (Da):36,431
Last modified:October 31, 1996 - v1
Checksum:i98DD6447F5A8C1B2
GO
Isoform 2 (identifier: Q16651-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     60-113: Missing.

Note: No experimental confirmation available.

Show »
Length:289
Mass (Da):30,519
Checksum:i4A85CFA9DE10BCDD
GO

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei60 – 11354Missing in isoform 2. 1 PublicationVSP_056632Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L41351 mRNA. Translation: AAC41759.1.
U33446 Genomic DNA. Translation: AAB19071.1.
AK301619 mRNA. Translation: BAG63104.1.
AC009088 Genomic DNA. No translation available.
BC001462 mRNA. Translation: AAH01462.1.
CCDSiCCDS45469.1. [Q16651-1]
PIRiA57014.
RefSeqiNP_002764.1. NM_002773.3. [Q16651-1]
UniGeneiHs.75799.

Genome annotation databases

EnsembliENST00000317508; ENSP00000319730; ENSG00000052344. [Q16651-1]
ENST00000568261; ENSP00000457750; ENSG00000052344. [Q16651-2]
GeneIDi5652.
KEGGihsa:5652.
UCSCiuc002ebc.4. human. [Q16651-1]

Polymorphism databases

DMDMi2833277.

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Web resourcesi

Atlas of Genetics and Cytogenetics in Oncology and Haematology

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L41351 mRNA. Translation: AAC41759.1.
U33446 Genomic DNA. Translation: AAB19071.1.
AK301619 mRNA. Translation: BAG63104.1.
AC009088 Genomic DNA. No translation available.
BC001462 mRNA. Translation: AAH01462.1.
CCDSiCCDS45469.1. [Q16651-1]
PIRiA57014.
RefSeqiNP_002764.1. NM_002773.3. [Q16651-1]
UniGeneiHs.75799.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
3DFJX-ray1.45A45-289[»]
3DFLX-ray2.00A45-289[»]
3E0NX-ray1.70B45-305[»]
3E0PX-ray1.70B45-305[»]
3E16X-ray1.60B45-305[»]
3E1XX-ray1.70B45-305[»]
3FVFX-ray1.60B45-305[»]
3GYLX-ray1.30B45-305[»]
3GYMX-ray2.80A/B45-305[»]
ProteinModelPortaliQ16651.
SMRiQ16651. Positions 45-289.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

IntActiQ16651. 1 interaction.
MINTiMINT-5000236.
STRINGi9606.ENSP00000319730.

Chemistry

BindingDBiQ16651.
ChEMBLiCHEMBL5610.
GuidetoPHARMACOLOGYi2400.

Protein family/group databases

MEROPSiS01.159.

Polymorphism databases

DMDMi2833277.

Proteomic databases

MaxQBiQ16651.
PaxDbiQ16651.
PRIDEiQ16651.

Protocols and materials databases

DNASUi5652.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000317508; ENSP00000319730; ENSG00000052344. [Q16651-1]
ENST00000568261; ENSP00000457750; ENSG00000052344. [Q16651-2]
GeneIDi5652.
KEGGihsa:5652.
UCSCiuc002ebc.4. human. [Q16651-1]

Organism-specific databases

CTDi5652.
GeneCardsiGC16M031142.
HGNCiHGNC:9491. PRSS8.
HPAiHPA030436.
MIMi600823. gene.
neXtProtiNX_Q16651.
PharmGKBiPA33840.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG5640.
GeneTreeiENSGT00760000118810.
HOGENOMiHOG000251820.
HOVERGENiHBG013304.
InParanoidiQ16651.
KOiK08664.
OMAiACGARNR.
OrthoDBiEOG75B84T.
PhylomeDBiQ16651.
TreeFamiTF351676.

Enzyme and pathway databases

BRENDAi3.4.21.B6. 2681.

Miscellaneous databases

ChiTaRSiPRSS8. human.
EvolutionaryTraceiQ16651.
GeneWikiiPRSS8.
GenomeRNAii5652.
NextBioi21962.
PROiQ16651.
SOURCEiSearch...

Gene expression databases

BgeeiQ16651.
CleanExiHS_PRSS8.
ExpressionAtlasiQ16651. baseline and differential.
GenevestigatoriQ16651.

Family and domain databases

InterProiIPR001254. Peptidase_S1.
IPR018114. Peptidase_S1_AS.
IPR001314. Peptidase_S1A.
IPR009003. Trypsin-like_Pept_dom.
[Graphical view]
PfamiPF00089. Trypsin. 1 hit.
[Graphical view]
PRINTSiPR00722. CHYMOTRYPSIN.
SMARTiSM00020. Tryp_SPc. 1 hit.
[Graphical view]
SUPFAMiSSF50494. SSF50494. 1 hit.
PROSITEiPS50240. TRYPSIN_DOM. 1 hit.
PS00134. TRYPSIN_HIS. 1 hit.
PS00135. TRYPSIN_SER. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Molecular cloning, tissue-specific expression, and cellular localization of human prostasin mRNA."
    Yu J.X., Chao L., Chao J.
    J. Biol. Chem. 270:13483-13489(1994) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORM 1), PARTIAL PROTEIN SEQUENCE.
    Tissue: Prostate.
  2. "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(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
    Tissue: Colon.
  3. "The sequence and analysis of duplication-rich human chromosome 16."
    Martin J., Han C., Gordon L.A., Terry A., Prabhakar S., She X., Xie G., Hellsten U., Chan Y.M., Altherr M., Couronne O., Aerts A., Bajorek E., Black S., Blumer H., Branscomb E., Brown N.C., Bruno W.J.
    , Buckingham J.M., Callen D.F., Campbell C.S., Campbell M.L., Campbell E.W., Caoile C., Challacombe J.F., Chasteen L.A., Chertkov O., Chi H.C., Christensen M., Clark L.M., Cohn J.D., Denys M., Detter J.C., Dickson M., Dimitrijevic-Bussod M., Escobar J., Fawcett J.J., Flowers D., Fotopulos D., Glavina T., Gomez M., Gonzales E., Goodstein D., Goodwin L.A., Grady D.L., Grigoriev I., Groza M., Hammon N., Hawkins T., Haydu L., Hildebrand C.E., Huang W., Israni S., Jett J., Jewett P.B., Kadner K., Kimball H., Kobayashi A., Krawczyk M.-C., Leyba T., Longmire J.L., Lopez F., Lou Y., Lowry S., Ludeman T., Manohar C.F., Mark G.A., McMurray K.L., Meincke L.J., Morgan J., Moyzis R.K., Mundt M.O., Munk A.C., Nandkeshwar R.D., Pitluck S., Pollard M., Predki P., Parson-Quintana B., Ramirez L., Rash S., Retterer J., Ricke D.O., Robinson D.L., Rodriguez A., Salamov A., Saunders E.H., Scott D., Shough T., Stallings R.L., Stalvey M., Sutherland R.D., Tapia R., Tesmer J.G., Thayer N., Thompson L.S., Tice H., Torney D.C., Tran-Gyamfi M., Tsai M., Ulanovsky L.E., Ustaszewska A., Vo N., White P.S., Williams A.L., Wills P.L., Wu J.-R., Wu K., Yang J., DeJong P., Bruce D., Doggett N.A., Deaven L., Schmutz J., Grimwood J., Richardson P., Rokhsar D.S., Eichler E.E., Gilna P., Lucas S.M., Myers R.M., Rubin E.M., Pennacchio L.A.
    Nature 432:988-994(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  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(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Placenta.
  5. "Prostasin is a novel human serine proteinase from seminal fluid. Purification, tissue distribution, and localization in prostate gland."
    Yu J.X., Chao L., Chao J.
    J. Biol. Chem. 269:18843-18848(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 45-64.
    Tissue: Semen.
  6. "Prostasin, a membrane-anchored serine peptidase, regulates sodium currents in JME/CF15 cells, a cystic fibrosis airway epithelial cell line."
    Tong Z., Illek B., Bhagwandin V.J., Verghese G.M., Caughey G.H.
    Am. J. Physiol. 287:L928-L935(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION IN SODIUM CHANNELS ACTIVATION.
  7. "Biochemical characterization of prostasin, a channel activating protease."
    Shipway A., Danahay H., Williams J.A., Tully D.C., Backes B.J., Harris J.L.
    Biochem. Biophys. Res. Commun. 324:953-963(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, SUBSTRATE SPECIFICITY.
  8. "Active site conformational changes of prostasin provide a new mechanism of protease regulation by divalent cations."
    Spraggon G., Hornsby M., Shipway A., Tully D.C., Bursulaya B., Danahay H., Harris J.L., Lesley S.A.
    Protein Sci. 18:1081-1094(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (1.3 ANGSTROMS) OF 45-305 IN COMPLEX WITH INHIBITOR, DISULFIDE BONDS.

Entry informationi

Entry nameiPRSS8_HUMAN
AccessioniPrimary (citable) accession number: Q16651
Secondary accession number(s): B4DWP2, Q9UCA3
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 31, 1997
Last sequence update: October 31, 1996
Last modified: March 31, 2015
This is version 134 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 16
    Human chromosome 16: 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. Peptidase families
    Classification of peptidase families and list of entries
  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.