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Protein

Vascular endothelial growth factor C

Gene

VEGFC

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

Functioni

Growth factor active in angiogenesis, and endothelial cell growth, stimulating their proliferation and migration and also has effects on the permeability of blood vessels. May function in angiogenesis of the venous and lymphatic vascular systems during embryogenesis, and also in the maintenance of differentiated lymphatic endothelium in adults. Binds and activates VEGFR-2 (KDR/FLK1) and VEGFR-3 (FLT4) receptors.1 Publication

GO - Molecular functioni

  • chemoattractant activity Source: UniProtKB

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Developmental protein, Growth factor, Mitogen

Keywords - Biological processi

Angiogenesis, Differentiation

Enzyme and pathway databases

ReactomeiREACT_12380. VEGF ligand-receptor interactions.
REACT_12583. VEGF binds to VEGFR leading to receptor dimerization.
REACT_318. Platelet degranulation.

Protein family/group databases

TCDBi9.B.88.2.1. the selenoprotein p hydrogen selenide uptake protein (selp) family.

Names & Taxonomyi

Protein namesi
Recommended name:
Vascular endothelial growth factor C
Short name:
VEGF-C
Alternative name(s):
Flt4 ligand
Short name:
Flt4-L
Vascular endothelial growth factor-related protein
Short name:
VRP
Gene namesi
Name:VEGFC
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 4

Organism-specific databases

HGNCiHGNC:12682. VEGFC.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Secreted

Pathology & Biotechi

Involvement in diseasei

Lymphedema, hereditary, 1D (LMPH1D)2 Publications

The disease is caused by mutations affecting the gene represented in this entry.

Disease descriptionA chronic disabling condition which results in swelling of the extremities due to altered lymphatic flow. Patients with lymphedema suffer from recurrent local infections and physical impairment.

See also OMIM:615907

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi227 – 2271R → S: No proteolytic processing and lower effect on VEGFR-2 and VEGFR-3. 1 Publication

Organism-specific databases

MIMi615907. phenotype.
Orphaneti79452. Milroy disease.
PharmGKBiPA37304.

Polymorphism and mutation databases

DMDMi1718154.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Signal peptidei1 – 31312 PublicationsAdd
BLAST
Propeptidei32 – 11180Or 1021 PublicationPRO_0000023400Add
BLAST
Chaini112 – 227116Vascular endothelial growth factor CPRO_0000023401Add
BLAST
Propeptidei228 – 419192PRO_0000023402Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi131 ↔ 1731 Publication
Disulfide bondi156 – 156Interchain1 Publication
Disulfide bondi162 ↔ 2091 Publication
Disulfide bondi165 – 165Interchain1 Publication
Disulfide bondi166 ↔ 2111 Publication
Glycosylationi175 – 1751N-linked (GlcNAc...)1 Publication
Glycosylationi205 – 2051N-linked (GlcNAc...)1 Publication
Glycosylationi240 – 2401N-linked (GlcNAc...)Sequence Analysis

Post-translational modificationi

Undergoes a complex proteolytic maturation which generates a variety of processed secreted forms with increased activity toward VEGFR-3, but only the fully processed form could activate VEGFR-2. VEGF-C first form an antiparallel homodimer linked by disulfide bonds. Before secretion, a cleavage occurs between Arg-227 and Ser-228 producing a heterotetramer. The next extracellular step of the processing removes the N-terminal propeptide. Finally the mature VEGF-C is composed mostly of two VEGF homology domains (VHDs) bound by non-covalent interactions.

Keywords - PTMi

Cleavage on pair of basic residues, Disulfide bond, Glycoprotein

Proteomic databases

PaxDbiP49767.
PRIDEiP49767.

PTM databases

PhosphoSiteiP49767.

Miscellaneous databases

PMAP-CutDBP49767.

Expressioni

Tissue specificityi

Spleen, lymph node, thymus, appendix, bone marrow, heart, placenta, ovary, skeletal muscle, prostate, testis, colon and small intestine and fetal liver, lung and kidney, but not in peripheral blood lymphocyte.

Gene expression databases

BgeeiP49767.
CleanExiHS_VEGFC.
GenevisibleiP49767. HS.

Interactioni

Subunit structurei

Homodimer; non-covalent and antiparallel.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
FLT4P359162EBI-3405539,EBI-1005467

Protein-protein interaction databases

BioGridi113267. 2 interactions.
DIPiDIP-5738N.
IntActiP49767. 1 interaction.
STRINGi9606.ENSP00000280193.

Structurei

Secondary structure

1
419
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi117 – 12913Combined sources
Beta strandi130 – 13910Combined sources
Turni140 – 1423Combined sources
Beta strandi151 – 16313Combined sources
Beta strandi167 – 1704Combined sources
Beta strandi172 – 18817Combined sources
Beta strandi190 – 1945Combined sources
Beta strandi197 – 21216Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2X1WX-ray2.70A/B/C/D112-215[»]
2X1XX-ray3.10E112-215[»]
4BSKX-ray4.20C103-215[»]
ProteinModelPortaliP49767.
SMRiP49767. Positions 117-215.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP49767.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Repeati280 – 295161Add
BLAST
Repeati304 – 319162Add
BLAST
Repeati328 – 343163Add
BLAST
Repeati347 – 362164Add
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni280 – 362834 X 16 AA repeats of C-X(10)-C-X-C-X(1,3)-CAdd
BLAST

Sequence similaritiesi

Belongs to the PDGF/VEGF growth factor family.Curated

Keywords - Domaini

Repeat, Signal

Phylogenomic databases

eggNOGiNOG79308.
GeneTreeiENSGT00730000110889.
HOGENOMiHOG000231512.
HOVERGENiHBG073119.
InParanoidiP49767.
KOiK05449.
OMAiTCPRNQP.
OrthoDBiEOG7J17ZS.
PhylomeDBiP49767.
TreeFamiTF319554.

Family and domain databases

Gene3Di2.10.90.10. 1 hit.
InterProiIPR004153. CXCXC_repeat.
IPR029034. Cystine-knot_cytokine.
IPR023581. PD_growth_factor_CS.
IPR000072. PDGF/VEGF_dom.
[Graphical view]
PfamiPF03128. CXCXC. 3 hits.
PF00341. PDGF. 1 hit.
[Graphical view]
SMARTiSM00141. PDGF. 1 hit.
[Graphical view]
SUPFAMiSSF57501. SSF57501. 1 hit.
PROSITEiPS00249. PDGF_1. 1 hit.
PS50278. PDGF_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

P49767-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MHLLGFFSVA CSLLAAALLP GPREAPAAAA AFESGLDLSD AEPDAGEATA
60 70 80 90 100
YASKDLEEQL RSVSSVDELM TVLYPEYWKM YKCQLRKGGW QHNREQANLN
110 120 130 140 150
SRTEETIKFA AAHYNTEILK SIDNEWRKTQ CMPREVCIDV GKEFGVATNT
160 170 180 190 200
FFKPPCVSVY RCGGCCNSEG LQCMNTSTSY LSKTLFEITV PLSQGPKPVT
210 220 230 240 250
ISFANHTSCR CMSKLDVYRQ VHSIIRRSLP ATLPQCQAAN KTCPTNYMWN
260 270 280 290 300
NHICRCLAQE DFMFSSDAGD DSTDGFHDIC GPNKELDEET CQCVCRAGLR
310 320 330 340 350
PASCGPHKEL DRNSCQCVCK NKLFPSQCGA NREFDENTCQ CVCKRTCPRN
360 370 380 390 400
QPLNPGKCAC ECTESPQKCL LKGKKFHHQT CSCYRRPCTN RQKACEPGFS
410
YSEEVCRCVP SYWKRPQMS
Length:419
Mass (Da):46,883
Last modified:October 1, 1996 - v1
Checksum:i9F598719DB3E014F
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X94216 mRNA. Translation: CAA63907.1.
U43142 mRNA. Translation: AAA85214.1.
U58111 mRNA. Translation: AAB02909.1.
AK313879 mRNA. Translation: BAG36605.1.
AC092673 Genomic DNA. No translation available.
AC093801 Genomic DNA. No translation available.
CH471056 Genomic DNA. Translation: EAX04717.1.
BC035212 mRNA. Translation: AAH35212.1.
BC063685 mRNA. Translation: AAH63685.1.
CCDSiCCDS43285.1.
PIRiS69207.
RefSeqiNP_005420.1. NM_005429.4.
UniGeneiHs.435215.

Genome annotation databases

EnsembliENST00000618562; ENSP00000480043; ENSG00000150630.
GeneIDi7424.
KEGGihsa:7424.
UCSCiuc003ius.1. human.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X94216 mRNA. Translation: CAA63907.1.
U43142 mRNA. Translation: AAA85214.1.
U58111 mRNA. Translation: AAB02909.1.
AK313879 mRNA. Translation: BAG36605.1.
AC092673 Genomic DNA. No translation available.
AC093801 Genomic DNA. No translation available.
CH471056 Genomic DNA. Translation: EAX04717.1.
BC035212 mRNA. Translation: AAH35212.1.
BC063685 mRNA. Translation: AAH63685.1.
CCDSiCCDS43285.1.
PIRiS69207.
RefSeqiNP_005420.1. NM_005429.4.
UniGeneiHs.435215.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2X1WX-ray2.70A/B/C/D112-215[»]
2X1XX-ray3.10E112-215[»]
4BSKX-ray4.20C103-215[»]
ProteinModelPortaliP49767.
SMRiP49767. Positions 117-215.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi113267. 2 interactions.
DIPiDIP-5738N.
IntActiP49767. 1 interaction.
STRINGi9606.ENSP00000280193.

Protein family/group databases

TCDBi9.B.88.2.1. the selenoprotein p hydrogen selenide uptake protein (selp) family.

PTM databases

PhosphoSiteiP49767.

Polymorphism and mutation databases

DMDMi1718154.

Proteomic databases

PaxDbiP49767.
PRIDEiP49767.

Protocols and materials databases

DNASUi7424.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000618562; ENSP00000480043; ENSG00000150630.
GeneIDi7424.
KEGGihsa:7424.
UCSCiuc003ius.1. human.

Organism-specific databases

CTDi7424.
GeneCardsiGC04M177604.
HGNCiHGNC:12682. VEGFC.
MIMi601528. gene.
615907. phenotype.
neXtProtiNX_P49767.
Orphaneti79452. Milroy disease.
PharmGKBiPA37304.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG79308.
GeneTreeiENSGT00730000110889.
HOGENOMiHOG000231512.
HOVERGENiHBG073119.
InParanoidiP49767.
KOiK05449.
OMAiTCPRNQP.
OrthoDBiEOG7J17ZS.
PhylomeDBiP49767.
TreeFamiTF319554.

Enzyme and pathway databases

ReactomeiREACT_12380. VEGF ligand-receptor interactions.
REACT_12583. VEGF binds to VEGFR leading to receptor dimerization.
REACT_318. Platelet degranulation.

Miscellaneous databases

ChiTaRSiVEGFC. human.
EvolutionaryTraceiP49767.
GeneWikiiVascular_endothelial_growth_factor_C.
GenomeRNAii7424.
NextBioi29082.
PMAP-CutDBP49767.
PROiP49767.
SOURCEiSearch...

Gene expression databases

BgeeiP49767.
CleanExiHS_VEGFC.
GenevisibleiP49767. HS.

Family and domain databases

Gene3Di2.10.90.10. 1 hit.
InterProiIPR004153. CXCXC_repeat.
IPR029034. Cystine-knot_cytokine.
IPR023581. PD_growth_factor_CS.
IPR000072. PDGF/VEGF_dom.
[Graphical view]
PfamiPF03128. CXCXC. 3 hits.
PF00341. PDGF. 1 hit.
[Graphical view]
SMARTiSM00141. PDGF. 1 hit.
[Graphical view]
SUPFAMiSSF57501. SSF57501. 1 hit.
PROSITEiPS00249. PDGF_1. 1 hit.
PS50278. PDGF_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "A novel vascular endothelial growth factor, VEGF-C, is a ligand for the Flt4 (VEGFR-3) and KDR (VEGFR-2) receptor tyrosine kinases."
    Joukov V., Pajusola K., Kaipainen A., Chilov D., Lahtinen I., Kukk E., Saksela O., Kalkkinen N., Alitalo K.
    EMBO J. 15:290-298(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 103-120.
  2. "Vascular endothelial growth factor-related protein: a ligand and specific activator of the tyrosine kinase receptor Flt4."
    Lee J., Gray A., Yuan J., Luoh S.-M., Avraham H., Wood W.I.
    Proc. Natl. Acad. Sci. U.S.A. 93:1988-1992(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
    Tissue: Glial tumor.
  3. Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  4. "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].
    Tissue: Trachea.
  5. "Generation and annotation of the DNA sequences of human chromosomes 2 and 4."
    Hillier L.W., Graves T.A., Fulton R.S., Fulton L.A., Pepin K.H., Minx P., Wagner-McPherson C., Layman D., Wylie K., Sekhon M., Becker M.C., Fewell G.A., Delehaunty K.D., Miner T.L., Nash W.E., Kremitzki C., Oddy L., Du H.
    , Sun H., Bradshaw-Cordum H., Ali J., Carter J., Cordes M., Harris A., Isak A., van Brunt A., Nguyen C., Du F., Courtney L., Kalicki J., Ozersky P., Abbott S., Armstrong J., Belter E.A., Caruso L., Cedroni M., Cotton M., Davidson T., Desai A., Elliott G., Erb T., Fronick C., Gaige T., Haakenson W., Haglund K., Holmes A., Harkins R., Kim K., Kruchowski S.S., Strong C.M., Grewal N., Goyea E., Hou S., Levy A., Martinka S., Mead K., McLellan M.D., Meyer R., Randall-Maher J., Tomlinson C., Dauphin-Kohlberg S., Kozlowicz-Reilly A., Shah N., Swearengen-Shahid S., Snider J., Strong J.T., Thompson J., Yoakum M., Leonard S., Pearman C., Trani L., Radionenko M., Waligorski J.E., Wang C., Rock S.M., Tin-Wollam A.-M., Maupin R., Latreille P., Wendl M.C., Yang S.-P., Pohl C., Wallis J.W., Spieth J., Bieri T.A., Berkowicz N., Nelson J.O., Osborne J., Ding L., Meyer R., Sabo A., Shotland Y., Sinha P., Wohldmann P.E., Cook L.L., Hickenbotham M.T., Eldred J., Williams D., Jones T.A., She X., Ciccarelli F.D., Izaurralde E., Taylor J., Schmutz J., Myers R.M., Cox D.R., Huang X., McPherson J.D., Mardis E.R., Clifton S.W., Warren W.C., Chinwalla A.T., Eddy S.R., Marra M.A., Ovcharenko I., Furey T.S., Miller W., Eichler E.E., Bork P., Suyama M., Torrents D., Waterston R.H., Wilson R.K.
    Nature 434:724-731(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  6. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  7. "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].
    Tissue: Skin and Urinary bladder.
  8. "Proteolytic processing regulates receptor specificity and activity of VEGF-C."
    Joukov V., Sorsa T., Kumar V., Jeltsch M., Claesson-Welsh L., Cao Y., Saksela O., Kalkkinen N., Alitalo K.
    EMBO J. 16:3898-3911(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 32-41; 112-121 AND 228-233, MUTAGENESIS OF ARG-227.
  9. "Signal peptide prediction based on analysis of experimentally verified cleavage sites."
    Zhang Z., Henzel W.J.
    Protein Sci. 13:2819-2824(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 32-46.
  10. "Mutation in vascular endothelial growth factor-C, a ligand for vascular endothelial growth factor receptor-3, is associated with autosomal dominant milroy-like primary lymphedema."
    Gordon K., Schulte D., Brice G., Simpson M.A., Roukens M.G., van Impel A., Connell F., Kalidas K., Jeffery S., Mortimer P.S., Mansour S., Schulte-Merker S., Ostergaard P.
    Circ. Res. 112:956-960(2013) [PubMed] [Europe PMC] [Abstract]
    Cited for: INVOLVEMENT IN LMPH1D.
  11. "A novel stop mutation in the vascular endothelial growth factor-C gene (VEGFC) results in Milroy-like disease."
    Balboa-Beltran E., Fernandez-Seara M.J., Perez-Munuzuri A., Lago R., Garcia-Magan C., Couce M.L., Sobrino B., Amigo J., Carracedo A., Barros F.
    J. Med. Genet. 51:475-478(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: INVOLVEMENT IN LMPH1D.
  12. Cited for: X-RAY CRYSTALLOGRAPHY (2.7 ANGSTROMS) OF 112-215 IN COMPLEX WITH KDR, FUNCTION, DISULFIDE BONDS, GLYCOSYLATION AT ASN-175 AND ASN-205, SUBUNIT.

Entry informationi

Entry nameiVEGFC_HUMAN
AccessioniPrimary (citable) accession number: P49767
Secondary accession number(s): B2R9Q8
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 1, 1996
Last sequence update: October 1, 1996
Last modified: July 22, 2015
This is version 140 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 4
    Human chromosome 4: 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.