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Protein

Sex-determining region Y protein

Gene

SRY

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

Functioni

Transcriptional regulator that controls a genetic switch in male development. It is necessary and sufficient for initiating male sex determination by directing the development of supporting cell precursors (pre-Sertoli cells) as Sertoli rather than granulosa cells (By similarity). In male adult brain involved in the maintenance of motor functions of dopaminergic neurons (By similarity). Involved in different aspects of gene regulation including promoter activation or repression (By similarity). Promotes DNA bending. SRY HMG box recognizes DNA by partial intercalation in the minor groove. Also involved in pre-mRNA splicing. Binds to the DNA consensus sequence 5'-[AT]AACAA[AT]-3'.By similarity4 Publications

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
DNA bindingi60 – 128HMG boxPROSITE-ProRule annotationAdd BLAST69

GO - Molecular functioni

  • DNA binding Source: UniProtKB
  • transcription factor activity, RNA polymerase II distal enhancer sequence-specific binding Source: UniProtKB
  • transcription factor binding Source: UniProtKB

GO - Biological processi

  • cell differentiation Source: UniProtKB-KW
  • male sex determination Source: UniProtKB
  • positive regulation of male gonad development Source: UniProtKB
  • positive regulation of transcription, DNA-templated Source: UniProtKB
  • sex differentiation Source: UniProtKB-KW
  • transcription, DNA-templated Source: UniProtKB-KW
Complete GO annotation...

Keywords - Molecular functioni

Activator, Repressor

Keywords - Biological processi

Differentiation, Sexual differentiation, Transcription, Transcription regulation

Keywords - Ligandi

Calmodulin-binding, DNA-binding

Enzyme and pathway databases

BioCyciZFISH:G66-31827-MONOMER.
ReactomeiR-HSA-3769402. Deactivation of the beta-catenin transactivating complex.
SignaLinkiQ05066.
SIGNORiQ05066.

Names & Taxonomyi

Protein namesi
Recommended name:
Sex-determining region Y protein
Alternative name(s):
Testis-determining factor
Gene namesi
Name:SRY
Synonyms:TDF
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome Y

Organism-specific databases

HGNCiHGNC:11311. SRY.

Subcellular locationi

  • Nucleus speckle
  • Cytoplasm

  • Note: Colocalizes with SOX6 in speckles. Colocalizes with CAML in the nucleus. Colocalizes in the nucleus with ZNF208 isoform KRAB-O and tyrosine hydroxylase (TH) (By similarity).By similarity

GO - Cellular componenti

  • cytoplasm Source: UniProtKB-SubCell
  • nuclear speck Source: UniProtKB-SubCell
  • nucleoplasm Source: Reactome
  • nucleus Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Nucleus

Pathology & Biotechi

Involvement in diseasei

46,XY sex reversal 1 (SRXY1)24 Publications
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA condition characterized by male-to-female sex reversal in the presence of a normal 46,XY karyotype. Patients manifest rapid and early degeneration of their gonads, which are present in the adult as 'streak gonads', consisting mainly of fibrous tissue and variable amounts of ovarian stroma. As a result these patients do not develop secondary sexual characteristics at puberty. The external genitalia in these subjects are completely female, and Muellerian structures are normal.
See also OMIM:400044
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_0300193S → L in SRXY1. 1 Publication1
Natural variantiVAR_00371718S → N in SRXY1; partial; also in two patients with a Turner syndrome phenotype. 2 PublicationsCorresponds to variant rs104894971dbSNPEnsembl.1
Natural variantiVAR_00371860V → A in SRXY1. 1 PublicationCorresponds to variant rs764249635dbSNPEnsembl.1
Natural variantiVAR_00371960V → L in SRXY1. 2 PublicationsCorresponds to variant rs104894957dbSNPEnsembl.1
Natural variantiVAR_00372062R → G in SRXY1. 1 Publication1
Natural variantiVAR_00372164M → I in SRXY1; alters interaction with DNA and DNA bending. 2 PublicationsCorresponds to variant rs104894969dbSNPEnsembl.1
Natural variantiVAR_01729864M → R in SRXY1. 1 Publication1
Natural variantiVAR_01729967F → V in SRXY1. 1 Publication1
Natural variantiVAR_00372268I → T in SRXY1. 1 PublicationCorresponds to variant rs104894968dbSNPEnsembl.1
Natural variantiVAR_01730076R → S in SRXY1. 1 Publication1
Natural variantiVAR_00372378M → T in SRXY1. 1 Publication1
Natural variantiVAR_01730187N → Y in SRXY1. 1 Publication1
Natural variantiVAR_00372490I → M in SRXY1. 3 PublicationsCorresponds to variant rs104894959dbSNPEnsembl.1
Natural variantiVAR_00372591S → G in SRXY1. 1 Publication1
Natural variantiVAR_01730295G → E in SRXY1. 1 PublicationCorresponds to variant rs104894972dbSNPEnsembl.1
Natural variantiVAR_00372695G → R in SRXY1. 1 PublicationCorresponds to variant rs104894974dbSNPEnsembl.1
Natural variantiVAR_003727101L → H in SRXY1. 1 Publication1
Natural variantiVAR_003728106K → I in SRXY1. 1 PublicationCorresponds to variant rs104894964dbSNPEnsembl.1
Natural variantiVAR_003729108P → R in SRXY1. 1 Publication1
Natural variantiVAR_003730109F → S in SRXY1. 1 PublicationCorresponds to variant rs104894956dbSNPEnsembl.1
Natural variantiVAR_003731113A → T in SRXY1. 1 PublicationCorresponds to variant rs104894966dbSNPEnsembl.1
Natural variantiVAR_003732125P → L in SRXY1. 1 Publication1
Natural variantiVAR_003733127Y → C in SRXY1. 1 Publication1
Natural variantiVAR_017303127Y → F in SRXY1. 1 PublicationCorresponds to variant rs104894973dbSNPEnsembl.1
Natural variantiVAR_017304131P → R in SRXY1. 1 Publication1
Natural variantiVAR_003734133R → W in SRXY1. 1 PublicationCorresponds to variant rs104894976dbSNPEnsembl.1

A 45,X chromosomal aberration involving SRY is found in Turner syndrome, a disease characterized by gonadal dysgenesis with short stature, "streak gonads", variable abnormalities such as webbing of the neck, cubitus valgus, cardiac defects, low posterior hair line. The phenotype is female.

46,XX sex reversal 1 (SRXX1)2 Publications
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA condition in which male gonads develop in a genetic female (female to male sex reversal).
See also OMIM:400045

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi31 – 33SSS → AAA: Abolishes its phosphorylation by PKA. Does not enhance its DNA-binding activity. Abolishes stimulation of transcription repression. 1 Publication3
Mutagenesisi62R → G: Strongly reduces nuclear localization. Strongly reduces nuclear localization; when associated with W-133. Reduces interaction with KPNB1. Abolishes DNA-binding. 1 Publication1
Mutagenesisi64M → I: Abolishes nuclear localization. 1 Publication1
Mutagenesisi75R → N: Strongly reduces nuclear localization. Abolishes DNA-binding. Does not reduce interaction with KPNB1 and CAML. 2 Publications1
Mutagenesisi76R → P: Reduces nuclear localization. Reduces DNA-binding. Does not reduce interaction with KPNB1 and CAML. 2 Publications1
Mutagenesisi115K → R: Does not abolish acetylation activity. 1 Publication1
Mutagenesisi123K → R: Does not abolish acetylation. 1 Publication1
Mutagenesisi128K → R: Does not abolish acetylation. 1 Publication1
Mutagenesisi133R → W: Reduces nuclear localization. Strongly reduces nuclear localization; when associated with G-62. Reduces interaction with KPNB1. Does not reduce interaction with CAML. Does not abolish DNA-binding. 2 Publications1
Mutagenesisi134K → R: Does not abolish acetylation. 1 Publication1
Mutagenesisi136K → R: Abolishes acetylation. Does not abolish interaction with EP300. Does not abolish DNA-binding. Enhances cytoplasmic localization. Abolishes interaction with KPNB1. 1 Publication1

Keywords - Diseasei

Disease mutation

Organism-specific databases

DisGeNETi6736.
MalaCardsiSRY.
MIMi400044. phenotype.
400045. phenotype.
OpenTargetsiENSG00000184895.
Orphaneti1772. 45,X/46,XY mixed gonadal dysgenesis.
2138. 46,XX ovotesticular disorder of sex development.
393. 46,XX testicular disorder of sex development.
242. 46,XY complete gonadal dysgenesis.
251510. 46,XY partial gonadal dysgenesis.
PharmGKBiPA36135.

Polymorphism and mutation databases

DMDMi548983.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00000486711 – 204Sex-determining region Y proteinAdd BLAST204

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei136N6-acetyllysine1 Publication1

Post-translational modificationi

Phosphorylated on serine residues by PKA. Phosphorylation by PKA enhances its DNA-binding activity and stimulates transcription repression.1 Publication
Acetylation of Lys-136 contributes to its nuclear localization and enhances its interaction with KPNB1. Deacetylated by HDAC3.1 Publication
Poly-ADP-ribosylated by PARP1. ADP-ribosylation reduces its DNA-binding activity.

Keywords - PTMi

Acetylation, ADP-ribosylation

Proteomic databases

PaxDbiQ05066.
PRIDEiQ05066.

PTM databases

iPTMnetiQ05066.
PhosphoSitePlusiQ05066.

Expressioni

Gene expression databases

BgeeiENSG00000184895.
CleanExiHS_SRY.
ExpressionAtlasiQ05066. baseline and differential.
GenevisibleiQ05066. HS.

Interactioni

Subunit structurei

Interacts with CALM, EP300, HDAC3, KPNB1, ZNF208 isoform KRAB-O, PARP1, SLC9A3R2 and WT1. The interaction with EP300 modulates its DNA-binding activity. The interaction with KPNB1 is sensitive to dissociation by Ran in the GTP-bound form (By similarity). Interaction with PARP1 impaired its DNA-binding activity (By similarity).By similarity

GO - Molecular functioni

  • transcription factor binding Source: UniProtKB

Protein-protein interaction databases

BioGridi112614. 19 interactors.
IntActiQ05066. 1 interactor.
MINTiMINT-1367278.
STRINGi9606.ENSP00000372547.

Structurei

Secondary structure

1204
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi66 – 81Combined sources16
Beta strandi86 – 88Combined sources3
Helixi89 – 99Combined sources11
Helixi103 – 123Combined sources21
Beta strandi124 – 126Combined sources3

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1HRYNMR-A56-131[»]
1HRZNMR-A56-131[»]
1J46NMR-A57-140[»]
1J47NMR-A57-140[»]
2GZKNMR-A56-130[»]
ProteinModelPortaliQ05066.
SMRiQ05066.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ05066.

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni59 – 136Sufficient for interaction with KPNB1Add BLAST78
Regioni61 – 77Required for nuclear localizationAdd BLAST17
Regioni107 – 139Sufficient for interaction with EP3001 PublicationAdd BLAST33
Regioni130 – 136Required for nuclear localization7
Regioni138 – 155Necessary for interaction with ZNF208 isoform KRAB-OAdd BLAST18
Regioni198 – 204Necessary for interaction with SLC9A3R21 Publication7

Domaini

DNA binding and bending properties of the HMG domains of human and mouse SRY differ form each other. Human SRY shows more extensive minor groove contacts with DNA and a lower specificity of sequence recognition than mouse SRY.

Sequence similaritiesi

Belongs to the SRY family.Curated
Contains 1 HMG box DNA-binding domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiKOG0527. Eukaryota.
ENOG410XT0K. LUCA.
GeneTreeiENSGT00760000118988.
HOGENOMiHOG000008601.
HOVERGENiHBG008712.
InParanoidiQ05066.
KOiK09266.
OMAiVWSRDQR.
OrthoDBiEOG091G0JDD.
PhylomeDBiQ05066.

Family and domain databases

Gene3Di1.10.30.10. 1 hit.
InterProiIPR009071. HMG_box_dom.
IPR017253. SRY.
[Graphical view]
PANTHERiPTHR10270:SF199. PTHR10270:SF199. 1 hit.
PfamiPF00505. HMG_box. 1 hit.
[Graphical view]
PIRSFiPIRSF037653. SRY. 1 hit.
SMARTiSM00398. HMG. 1 hit.
[Graphical view]
SUPFAMiSSF47095. SSF47095. 1 hit.
PROSITEiPS50118. HMG_BOX_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Q05066-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MQSYASAMLS VFNSDDYSPA VQENIPALRR SSSFLCTESC NSKYQCETGE
60 70 80 90 100
NSKGNVQDRV KRPMNAFIVW SRDQRRKMAL ENPRMRNSEI SKQLGYQWKM
110 120 130 140 150
LTEAEKWPFF QEAQKLQAMH REKYPNYKYR PRRKAKMLPK NCSLLPADPA
160 170 180 190 200
SVLCSEVQLD NRLYRDDCTK ATHSRMEHQL GHLPPINAAS SPQQRDRYSH

WTKL
Length:204
Mass (Da):23,884
Last modified:June 1, 1994 - v1
Checksum:i84323C30A9C2173E
GO

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_0300193S → L in SRXY1. 1 Publication1
Natural variantiVAR_00371718S → N in SRXY1; partial; also in two patients with a Turner syndrome phenotype. 2 PublicationsCorresponds to variant rs104894971dbSNPEnsembl.1
Natural variantiVAR_00371860V → A in SRXY1. 1 PublicationCorresponds to variant rs764249635dbSNPEnsembl.1
Natural variantiVAR_00371960V → L in SRXY1. 2 PublicationsCorresponds to variant rs104894957dbSNPEnsembl.1
Natural variantiVAR_00372062R → G in SRXY1. 1 Publication1
Natural variantiVAR_00372164M → I in SRXY1; alters interaction with DNA and DNA bending. 2 PublicationsCorresponds to variant rs104894969dbSNPEnsembl.1
Natural variantiVAR_01729864M → R in SRXY1. 1 Publication1
Natural variantiVAR_01729967F → V in SRXY1. 1 Publication1
Natural variantiVAR_00372268I → T in SRXY1. 1 PublicationCorresponds to variant rs104894968dbSNPEnsembl.1
Natural variantiVAR_01730076R → S in SRXY1. 1 Publication1
Natural variantiVAR_00372378M → T in SRXY1. 1 Publication1
Natural variantiVAR_01730187N → Y in SRXY1. 1 Publication1
Natural variantiVAR_00372490I → M in SRXY1. 3 PublicationsCorresponds to variant rs104894959dbSNPEnsembl.1
Natural variantiVAR_00372591S → G in SRXY1. 1 Publication1
Natural variantiVAR_01730295G → E in SRXY1. 1 PublicationCorresponds to variant rs104894972dbSNPEnsembl.1
Natural variantiVAR_00372695G → R in SRXY1. 1 PublicationCorresponds to variant rs104894974dbSNPEnsembl.1
Natural variantiVAR_003727101L → H in SRXY1. 1 Publication1
Natural variantiVAR_003728106K → I in SRXY1. 1 PublicationCorresponds to variant rs104894964dbSNPEnsembl.1
Natural variantiVAR_003729108P → R in SRXY1. 1 Publication1
Natural variantiVAR_003730109F → S in SRXY1. 1 PublicationCorresponds to variant rs104894956dbSNPEnsembl.1
Natural variantiVAR_003731113A → T in SRXY1. 1 PublicationCorresponds to variant rs104894966dbSNPEnsembl.1
Natural variantiVAR_003732125P → L in SRXY1. 1 Publication1
Natural variantiVAR_003733127Y → C in SRXY1. 1 Publication1
Natural variantiVAR_017303127Y → F in SRXY1. 1 PublicationCorresponds to variant rs104894973dbSNPEnsembl.1
Natural variantiVAR_017304131P → R in SRXY1. 1 Publication1
Natural variantiVAR_003734133R → W in SRXY1. 1 PublicationCorresponds to variant rs104894976dbSNPEnsembl.1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X53772 Genomic DNA. Translation: CAA37790.1.
L10101 mRNA. Translation: AAA60590.1.
L10102 Genomic DNA. Translation: AAA60591.1.
L08063 Genomic DNA. Translation: AAA16878.1.
X96421 Genomic DNA. Translation: CAA65281.1.
S53156 mRNA. Translation: AAB25008.1.
S56543 mRNA. Translation: AAB25716.1.
BC074923 mRNA. Translation: AAH74923.1.
BC074924 mRNA. Translation: AAH74924.1.
CCDSiCCDS14772.1.
PIRiA47533.
RefSeqiNP_003131.1. NM_003140.2.
UniGeneiHs.1992.

Genome annotation databases

EnsembliENST00000383070; ENSP00000372547; ENSG00000184895.
GeneIDi6736.
KEGGihsa:6736.
UCSCiuc004fqg.3. human.

Keywords - Coding sequence diversityi

Chromosomal rearrangement

Cross-referencesi

Web resourcesi

Protein Spotlight

The tenuous nature of sex - Issue 80 of March 2007

Wikipedia

SRY entry

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X53772 Genomic DNA. Translation: CAA37790.1.
L10101 mRNA. Translation: AAA60590.1.
L10102 Genomic DNA. Translation: AAA60591.1.
L08063 Genomic DNA. Translation: AAA16878.1.
X96421 Genomic DNA. Translation: CAA65281.1.
S53156 mRNA. Translation: AAB25008.1.
S56543 mRNA. Translation: AAB25716.1.
BC074923 mRNA. Translation: AAH74923.1.
BC074924 mRNA. Translation: AAH74924.1.
CCDSiCCDS14772.1.
PIRiA47533.
RefSeqiNP_003131.1. NM_003140.2.
UniGeneiHs.1992.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1HRYNMR-A56-131[»]
1HRZNMR-A56-131[»]
1J46NMR-A57-140[»]
1J47NMR-A57-140[»]
2GZKNMR-A56-130[»]
ProteinModelPortaliQ05066.
SMRiQ05066.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi112614. 19 interactors.
IntActiQ05066. 1 interactor.
MINTiMINT-1367278.
STRINGi9606.ENSP00000372547.

PTM databases

iPTMnetiQ05066.
PhosphoSitePlusiQ05066.

Polymorphism and mutation databases

DMDMi548983.

Proteomic databases

PaxDbiQ05066.
PRIDEiQ05066.

Protocols and materials databases

DNASUi6736.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000383070; ENSP00000372547; ENSG00000184895.
GeneIDi6736.
KEGGihsa:6736.
UCSCiuc004fqg.3. human.

Organism-specific databases

CTDi6736.
DisGeNETi6736.
GeneCardsiSRY.
GeneReviewsiSRY.
HGNCiHGNC:11311. SRY.
MalaCardsiSRY.
MIMi400044. phenotype.
400045. phenotype.
480000. gene.
neXtProtiNX_Q05066.
OpenTargetsiENSG00000184895.
Orphaneti1772. 45,X/46,XY mixed gonadal dysgenesis.
2138. 46,XX ovotesticular disorder of sex development.
393. 46,XX testicular disorder of sex development.
242. 46,XY complete gonadal dysgenesis.
251510. 46,XY partial gonadal dysgenesis.
PharmGKBiPA36135.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG0527. Eukaryota.
ENOG410XT0K. LUCA.
GeneTreeiENSGT00760000118988.
HOGENOMiHOG000008601.
HOVERGENiHBG008712.
InParanoidiQ05066.
KOiK09266.
OMAiVWSRDQR.
OrthoDBiEOG091G0JDD.
PhylomeDBiQ05066.

Enzyme and pathway databases

BioCyciZFISH:G66-31827-MONOMER.
ReactomeiR-HSA-3769402. Deactivation of the beta-catenin transactivating complex.
SignaLinkiQ05066.
SIGNORiQ05066.

Miscellaneous databases

EvolutionaryTraceiQ05066.
GeneWikiiSRY.
GenomeRNAii6736.
PROiQ05066.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000184895.
CleanExiHS_SRY.
ExpressionAtlasiQ05066. baseline and differential.
GenevisibleiQ05066. HS.

Family and domain databases

Gene3Di1.10.30.10. 1 hit.
InterProiIPR009071. HMG_box_dom.
IPR017253. SRY.
[Graphical view]
PANTHERiPTHR10270:SF199. PTHR10270:SF199. 1 hit.
PfamiPF00505. HMG_box. 1 hit.
[Graphical view]
PIRSFiPIRSF037653. SRY. 1 hit.
SMARTiSM00398. HMG. 1 hit.
[Graphical view]
SUPFAMiSSF47095. SSF47095. 1 hit.
PROSITEiPS50118. HMG_BOX_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiSRY_HUMAN
AccessioniPrimary (citable) accession number: Q05066
Entry historyi
Integrated into UniProtKB/Swiss-Prot: June 1, 1994
Last sequence update: June 1, 1994
Last modified: November 2, 2016
This is version 178 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, Reference proteome

Documents

  1. Human chromosome Y
    Human chromosome Y: 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. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. Protein Spotlight
    Protein Spotlight articles and cited UniProtKB/Swiss-Prot entries
  7. 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.