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Protein

Guanidinoacetate N-methyltransferase

Gene

GAMT

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

Functioni

Converts guanidinoacetate to creatine, using S-adenosylmethionine as the methyl donor (PubMed:26003046, PubMed:24415674, PubMed:26319512). Important in nervous system development (PubMed:24415674).3 Publications

Catalytic activityi

S-adenosyl-L-methionine + guanidinoacetate = S-adenosyl-L-homocysteine + creatine.PROSITE-ProRule annotation

Pathwayi: creatine biosynthesis

This protein is involved in step 2 of the subpathway that synthesizes creatine from L-arginine and glycine.
Proteins known to be involved in the 2 steps of the subpathway in this organism are:
  1. Glycine amidinotransferase, mitochondrial (GATM)
  2. Guanidinoacetate N-methyltransferase (GAMT)
This subpathway is part of the pathway creatine biosynthesis, which is itself part of Amine and polyamine biosynthesis.
View all proteins of this organism that are known to be involved in the subpathway that synthesizes creatine from L-arginine and glycine, the pathway creatine biosynthesis and in Amine and polyamine biosynthesis.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei20S-adenosyl-L-methionine1
Binding sitei42SubstratePROSITE-ProRule annotation1
Binding sitei46SubstratePROSITE-ProRule annotation1
Binding sitei50S-adenosyl-L-methionine1
Binding sitei135S-adenosyl-L-methionine and substratePROSITE-ProRule annotation1

GO - Molecular functioni

  • guanidinoacetate N-methyltransferase activity Source: UniProtKB
  • methyltransferase activity Source: Reactome

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Methyltransferase, Transferase

Keywords - Ligandi

S-adenosyl-L-methionine

Enzyme and pathway databases

BioCyciMetaCyc:HS05327-MONOMER.
ZFISH:HS05327-MONOMER.
BRENDAi2.1.1.2. 2681.
ReactomeiR-HSA-71288. Creatine metabolism.
UniPathwayiUPA00104; UER00580.

Names & Taxonomyi

Protein namesi
Recommended name:
Guanidinoacetate N-methyltransferase (EC:2.1.1.2)
Gene namesi
Name:GAMT
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 19

Organism-specific databases

HGNCiHGNC:4136. GAMT.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: GO_Central
  • cytosol Source: Reactome
  • extracellular exosome Source: UniProtKB
  • nucleus Source: GO_Central
Complete GO annotation...

Pathology & Biotechi

Involvement in diseasei

Cerebral creatine deficiency syndrome 2 (CCDS2)11 Publications
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionAn autosomal recessive disorder characterized by developmental delay and regression, mental retardation, severe disturbance of expressive and cognitive speech, intractable seizures, movement disturbances, severe depletion of creatine and phosphocreatine in the brain, and accumulation of guanidinoacetic acid in brain and body fluids.
See also OMIM:612736
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_05810220W → S in CCDS2. 2 PublicationsCorresponds to variant rs80338734dbSNPEnsembl.1
Natural variantiVAR_07177745W → R in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_05810350M → L in CCDS2; retains no significant activity. 2 PublicationsCorresponds to variant rs104894694dbSNPEnsembl.1
Natural variantiVAR_05810451H → P in CCDS2; retains no significant activity. 3 Publications1
Natural variantiVAR_05810554A → P in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_07177868G → C in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_07177975A → V in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_07178078V → E in CCDS2. 1 Publication1
Natural variantiVAR_071781110V → F in CCDS2; retains no significant activity. 1 PublicationCorresponds to variant rs753198836dbSNPEnsembl.1
Natural variantiVAR_071782135D → N in CCDS2. 1 PublicationCorresponds to variant rs774144200dbSNPEnsembl.1
Natural variantiVAR_071783147H → Y in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_071784159L → P in CCDS2; loss of activity. 1 Publication1
Natural variantiVAR_071785164G → D in CCDS2. 1 PublicationCorresponds to variant rs760101382dbSNPEnsembl.1
Natural variantiVAR_071786166L → P in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_071787169C → R in CCDS2. 1 Publication1
Natural variantiVAR_058106169C → Y in CCDS2; retains no significant activity. 2 PublicationsCorresponds to variant rs121909272dbSNPEnsembl.1
Natural variantiVAR_058107197L → P in CCDS2; loss of activity. 3 Publications1
Natural variantiVAR_071788208R → P in CCDS2; retains no significant activity. 1 PublicationCorresponds to variant rs767887772dbSNPEnsembl.1

Keywords - Diseasei

Disease mutation

Organism-specific databases

DisGeNETi2593.
MalaCardsiGAMT.
MIMi612736. phenotype.
OpenTargetsiENSG00000130005.
Orphaneti382. Guanidinoacetate methyltransferase deficiency.
PharmGKBiPA28549.

Chemistry databases

DrugBankiDB00148. Creatine.
DB00536. Guanidine.

Polymorphism and mutation databases

BioMutaiGAMT.
DMDMi2498404.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemovedCombined sources
ChainiPRO_00000874302 – 236Guanidinoacetate N-methyltransferaseAdd BLAST235

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei2N-acetylserineCombined sources1

Keywords - PTMi

Acetylation

Proteomic databases

EPDiQ14353.
PaxDbiQ14353.
PeptideAtlasiQ14353.
PRIDEiQ14353.

2D gel databases

OGPiQ14353.

PTM databases

iPTMnetiQ14353.
PhosphoSitePlusiQ14353.

Expressioni

Tissue specificityi

Expressed in liver.1 Publication

Gene expression databases

BgeeiENSG00000130005.
CleanExiHS_GAMT.
ExpressionAtlasiQ14353. baseline and differential.
GenevisibleiQ14353. HS.

Organism-specific databases

HPAiHPA051806.

Interactioni

Subunit structurei

Monomer.By similarity

Protein-protein interaction databases

BioGridi108865. 8 interactors.
IntActiQ14353. 6 interactors.
STRINGi9606.ENSP00000403536.

Structurei

Secondary structure

1236
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi17 – 20Combined sources4
Beta strandi25 – 27Combined sources3
Beta strandi31 – 36Combined sources6
Beta strandi39 – 43Combined sources5
Helixi44 – 46Combined sources3
Helixi47 – 57Combined sources11
Turni58 – 60Combined sources3
Beta strandi62 – 67Combined sources6
Helixi73 – 78Combined sources6
Beta strandi83 – 90Combined sources8
Helixi93 – 102Combined sources10
Helixi103 – 105Combined sources3
Beta strandi107 – 115Combined sources9
Helixi117 – 120Combined sources4
Helixi121 – 123Combined sources3
Beta strandi129 – 134Combined sources6
Helixi141 – 143Combined sources3
Turni144 – 146Combined sources3
Helixi147 – 154Combined sources8
Helixi156 – 159Combined sources4
Beta strandi160 – 168Combined sources9
Helixi171 – 177Combined sources7
Turni178 – 181Combined sources4
Helixi185 – 192Combined sources8
Helixi194 – 200Combined sources7
Helixi204 – 206Combined sources3
Beta strandi207 – 213Combined sources7
Beta strandi226 – 234Combined sources9

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3ORHX-ray1.86A/B/C/D1-236[»]
ProteinModelPortaliQ14353.
SMRiQ14353.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ14353.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini13 – 236RMT2PROSITE-ProRule annotationAdd BLAST224

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni69 – 74S-adenosyl-L-methionine binding6
Regioni90 – 92S-adenosyl-L-methionine3
Regioni117 – 118S-adenosyl-L-methionine binding2
Regioni171 – 172Substrate binding2

Sequence similaritiesi

Belongs to the class I-like SAM-binding methyltransferase superfamily. RMT2 methyltransferase family.PROSITE-ProRule annotation
Contains 1 RMT2 (arginine N-methyltransferase 2-like) domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiKOG1709. Eukaryota.
ENOG4110T2S. LUCA.
GeneTreeiENSGT00390000018061.
HOGENOMiHOG000010290.
HOVERGENiHBG005801.
InParanoidiQ14353.
KOiK00542.
OMAiRYYAFPQ.
OrthoDBiEOG091G0EPW.
PhylomeDBiQ14353.
TreeFamiTF328555.

Family and domain databases

Gene3Di3.40.50.150. 1 hit.
InterProiIPR016550. GuanidinoAc_N-MeTrfase.
IPR026480. RMT2_dom.
IPR029063. SAM-dependent_MTases.
[Graphical view]
PIRSFiPIRSF009285. GAMT. 1 hit.
SUPFAMiSSF53335. SSF53335. 1 hit.
PROSITEiPS51559. SAM_RMT2. 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: Q14353-1) [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
MSAPSATPIF APGENCSPAW GAAPAAYDAA DTHLRILGKP VMERWETPYM
60 70 80 90 100
HALAAAASSK GGRVLEVGFG MAIAASKVQE APIDEHWIIE CNDGVFQRLR
110 120 130 140 150
DWAPRQTHKV IPLKGLWEDV APTLPDGHFD GILYDTYPLS EETWHTHQFN
160 170 180 190 200
FIKNHAFRLL KPGGVLTYCN LTSWGELMKS KYSDITIMFE ETQVPALLEA
210 220 230
GFRRENIRTE VMALVPPADC RYYAFPQMIT PLVTKG
Length:236
Mass (Da):26,318
Last modified:November 1, 1996 - v1
Checksum:i6B8E845CE56189F5
GO
Isoform 2 (identifier: Q14353-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     191-236: ETQVPALLEA...QMITPLVTKG → VRPPEVPHGS...TVEGRGGQIA

Note: No experimental confirmation available.
Show »
Length:269
Mass (Da):29,377
Checksum:iD04624287AE534A8
GO

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_0717758P → T Rare polymorphism; no effect on activity. 1 PublicationCorresponds to variant rs776498025dbSNPEnsembl.1
Natural variantiVAR_05810220W → S in CCDS2. 2 PublicationsCorresponds to variant rs80338734dbSNPEnsembl.1
Natural variantiVAR_07177627Y → H Polymorphism; no effect on activity. 1 PublicationCorresponds to variant rs200833152dbSNPEnsembl.1
Natural variantiVAR_07529044R → L Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs200339910dbSNPEnsembl.1
Natural variantiVAR_07177745W → R in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_05810350M → L in CCDS2; retains no significant activity. 2 PublicationsCorresponds to variant rs104894694dbSNPEnsembl.1
Natural variantiVAR_05810451H → P in CCDS2; retains no significant activity. 3 Publications1
Natural variantiVAR_05810554A → P in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_07177868G → C in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_07529171M → V Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs372027428dbSNPEnsembl.1
Natural variantiVAR_07177975A → V in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_07529276S → L Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs150338273dbSNPEnsembl.1
Natural variantiVAR_07178078V → E in CCDS2. 1 Publication1
Natural variantiVAR_07529378V → M Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs141358977dbSNPEnsembl.1
Natural variantiVAR_07529495V → I Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs140778208dbSNPEnsembl.1
Natural variantiVAR_075295105R → Q Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs148838075dbSNPEnsembl.1
Natural variantiVAR_075296106Q → P Disrupts enzymatic activity. 1 PublicationCorresponds to variant rs145817990dbSNPEnsembl.1
Natural variantiVAR_071781110V → F in CCDS2; retains no significant activity. 1 PublicationCorresponds to variant rs753198836dbSNPEnsembl.1
Natural variantiVAR_071782135D → N in CCDS2. 1 PublicationCorresponds to variant rs774144200dbSNPEnsembl.1
Natural variantiVAR_075297146T → R Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs149821870dbSNPEnsembl.1
Natural variantiVAR_071783147H → Y in CCDS2; retains no significant activity. 1 Publication1
Natural variantiVAR_075298156A → D Disrupts enzymatic activity. 1 PublicationCorresponds to variant rs368221789dbSNPEnsembl.1
Natural variantiVAR_075299157F → L Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs372260609dbSNPEnsembl.1
Natural variantiVAR_071784159L → P in CCDS2; loss of activity. 1 Publication1
Natural variantiVAR_071785164G → D in CCDS2. 1 PublicationCorresponds to variant rs760101382dbSNPEnsembl.1
Natural variantiVAR_071786166L → P in CCDS2; loss of activity. 2 Publications1
Natural variantiVAR_075300167T → I Disrupts enzymatic activity. 1 PublicationCorresponds to variant rs374762419dbSNPEnsembl.1
Natural variantiVAR_071787169C → R in CCDS2. 1 Publication1
Natural variantiVAR_058106169C → Y in CCDS2; retains no significant activity. 2 PublicationsCorresponds to variant rs121909272dbSNPEnsembl.1
Natural variantiVAR_075301196A → T Polymorphism; no effect on enzymatic activity. 1 Publication1
Natural variantiVAR_075302196A → V Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs565109128dbSNPEnsembl.1
Natural variantiVAR_058107197L → P in CCDS2; loss of activity. 3 Publications1
Natural variantiVAR_071788208R → P in CCDS2; retains no significant activity. 1 PublicationCorresponds to variant rs767887772dbSNPEnsembl.1
Natural variantiVAR_025723209T → M.1 PublicationCorresponds to variant rs17851582dbSNPEnsembl.1
Natural variantiVAR_075303224A → T Polymorphism; no effect on enzymatic activity. 1 PublicationCorresponds to variant rs141471799dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_042722191 – 236ETQVP…LVTKG → VRPPEVPHGSPGSDLGWGWE GAAGATLLPGEGPFLTPWVG WTVLVHLEIKVLCLAQWLPG AVAQVYNPSTVEGRGGQIA in isoform 2. 1 PublicationAdd BLAST46

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
Z49878 mRNA. Translation: CAA90035.1.
AF010248, AF010246, AF010247 Genomic DNA. Translation: AAD04781.1.
AF188893 Genomic DNA. Translation: AAF01461.1.
BT007034 mRNA. Translation: AAP35682.1.
AK289465 mRNA. Translation: BAF82154.1.
AC005329 Genomic DNA. Translation: AAC27668.1.
CH471139 Genomic DNA. Translation: EAW69505.1.
BC016760 mRNA. Translation: AAH16760.1.
BC017936 mRNA. Translation: AAH17936.1.
CCDSiCCDS12064.1. [Q14353-1]
CCDS45897.1. [Q14353-2]
PIRiS62732.
RefSeqiNP_000147.1. NM_000156.5. [Q14353-1]
NP_620279.1. NM_138924.2. [Q14353-2]
UniGeneiHs.81131.

Genome annotation databases

EnsembliENST00000252288; ENSP00000252288; ENSG00000130005. [Q14353-1]
ENST00000447102; ENSP00000403536; ENSG00000130005. [Q14353-2]
GeneIDi2593.
KEGGihsa:2593.
UCSCiuc002lsk.5. human. [Q14353-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
Z49878 mRNA. Translation: CAA90035.1.
AF010248, AF010246, AF010247 Genomic DNA. Translation: AAD04781.1.
AF188893 Genomic DNA. Translation: AAF01461.1.
BT007034 mRNA. Translation: AAP35682.1.
AK289465 mRNA. Translation: BAF82154.1.
AC005329 Genomic DNA. Translation: AAC27668.1.
CH471139 Genomic DNA. Translation: EAW69505.1.
BC016760 mRNA. Translation: AAH16760.1.
BC017936 mRNA. Translation: AAH17936.1.
CCDSiCCDS12064.1. [Q14353-1]
CCDS45897.1. [Q14353-2]
PIRiS62732.
RefSeqiNP_000147.1. NM_000156.5. [Q14353-1]
NP_620279.1. NM_138924.2. [Q14353-2]
UniGeneiHs.81131.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3ORHX-ray1.86A/B/C/D1-236[»]
ProteinModelPortaliQ14353.
SMRiQ14353.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi108865. 8 interactors.
IntActiQ14353. 6 interactors.
STRINGi9606.ENSP00000403536.

Chemistry databases

DrugBankiDB00148. Creatine.
DB00536. Guanidine.

PTM databases

iPTMnetiQ14353.
PhosphoSitePlusiQ14353.

Polymorphism and mutation databases

BioMutaiGAMT.
DMDMi2498404.

2D gel databases

OGPiQ14353.

Proteomic databases

EPDiQ14353.
PaxDbiQ14353.
PeptideAtlasiQ14353.
PRIDEiQ14353.

Protocols and materials databases

DNASUi2593.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000252288; ENSP00000252288; ENSG00000130005. [Q14353-1]
ENST00000447102; ENSP00000403536; ENSG00000130005. [Q14353-2]
GeneIDi2593.
KEGGihsa:2593.
UCSCiuc002lsk.5. human. [Q14353-1]

Organism-specific databases

CTDi2593.
DisGeNETi2593.
GeneCardsiGAMT.
GeneReviewsiGAMT.
H-InvDBHIX0030201.
HGNCiHGNC:4136. GAMT.
HPAiHPA051806.
MalaCardsiGAMT.
MIMi601240. gene.
612736. phenotype.
neXtProtiNX_Q14353.
OpenTargetsiENSG00000130005.
Orphaneti382. Guanidinoacetate methyltransferase deficiency.
PharmGKBiPA28549.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG1709. Eukaryota.
ENOG4110T2S. LUCA.
GeneTreeiENSGT00390000018061.
HOGENOMiHOG000010290.
HOVERGENiHBG005801.
InParanoidiQ14353.
KOiK00542.
OMAiRYYAFPQ.
OrthoDBiEOG091G0EPW.
PhylomeDBiQ14353.
TreeFamiTF328555.

Enzyme and pathway databases

UniPathwayiUPA00104; UER00580.
BioCyciMetaCyc:HS05327-MONOMER.
ZFISH:HS05327-MONOMER.
BRENDAi2.1.1.2. 2681.
ReactomeiR-HSA-71288. Creatine metabolism.

Miscellaneous databases

EvolutionaryTraceiQ14353.
GeneWikiiGuanidinoacetate_N-methyltransferase.
GenomeRNAii2593.
PROiQ14353.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000130005.
CleanExiHS_GAMT.
ExpressionAtlasiQ14353. baseline and differential.
GenevisibleiQ14353. HS.

Family and domain databases

Gene3Di3.40.50.150. 1 hit.
InterProiIPR016550. GuanidinoAc_N-MeTrfase.
IPR026480. RMT2_dom.
IPR029063. SAM-dependent_MTases.
[Graphical view]
PIRSFiPIRSF009285. GAMT. 1 hit.
SUPFAMiSSF53335. SSF53335. 1 hit.
PROSITEiPS51559. SAM_RMT2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiGAMT_HUMAN
AccessioniPrimary (citable) accession number: Q14353
Secondary accession number(s): A8K0A0, Q53Y34, Q8WVJ1
Entry historyi
Integrated into UniProtKB/Swiss-Prot: November 1, 1997
Last sequence update: November 1, 1996
Last modified: November 30, 2016
This is version 162 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 19
    Human chromosome 19: 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. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  6. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  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.