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Protein

Phosphoenolpyruvate carboxykinase, cytosolic [GTP]

Gene

PCK1

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

Functioni

Catalyzes the conversion of oxaloacetate (OAA) to phosphoenolpyruvate (PEP), the rate-limiting step in the metabolic pathway that produces glucose from lactate and other precursors derived from the citric acid cycle.

Catalytic activityi

GTP + oxaloacetate = GDP + phosphoenolpyruvate + CO2.

Cofactori

Mn2+3 PublicationsNote: Binds 1 Mn2+ ion per subunit.3 Publications

Enzyme regulationi

Enzyme activity is enhanced by acetylation.1 Publication

Pathwayi: gluconeogenesis

This protein is involved in the pathway gluconeogenesis, which is part of Carbohydrate biosynthesis.
View all proteins of this organism that are known to be involved in the pathway gluconeogenesis and in Carbohydrate biosynthesis.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei87Substrate3 Publications1
Metal bindingi244Manganese3 Publications1
Metal bindingi264Manganese; via tele nitrogen3 Publications1
Binding sitei286SubstrateBy similarity1
Active sitei2881 Publication1
Metal bindingi311Manganese3 Publications1
Binding sitei405GTP1 Publication1
Binding sitei436GTP1 Publication1

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Nucleotide bindingi287 – 292GTP1 Publication6
Nucleotide bindingi530 – 533GTP3 Publications4

GO - Molecular functioni

  • carboxylic acid binding Source: BHF-UCL
  • GDP binding Source: Ensembl
  • GTP binding Source: BHF-UCL
  • magnesium ion binding Source: BHF-UCL
  • manganese ion binding Source: BHF-UCL
  • nucleoside diphosphate kinase activity Source: Ensembl
  • phosphoenolpyruvate carboxykinase (GTP) activity Source: BHF-UCL

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Decarboxylase, Lyase

Keywords - Biological processi

Gluconeogenesis

Keywords - Ligandi

GTP-binding, Manganese, Metal-binding, Nucleotide-binding

Enzyme and pathway databases

BioCyciMetaCyc:HS04751-MONOMER.
ZFISH:HS04751-MONOMER.
BRENDAi4.1.1.32. 2681.
ReactomeiR-HSA-2161541. Abacavir metabolism.
R-HSA-381340. Transcriptional regulation of white adipocyte differentiation.
R-HSA-70263. Gluconeogenesis.
SABIO-RKP35558.
SIGNORiP35558.
UniPathwayiUPA00138.

Names & Taxonomyi

Protein namesi
Recommended name:
Phosphoenolpyruvate carboxykinase, cytosolic [GTP] (EC:4.1.1.32)
Short name:
PEPCK-C
Gene namesi
Name:PCK1Imported
Synonyms:PEPCK1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 20

Organism-specific databases

HGNCiHGNC:8724. PCK1.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: BHF-UCL
  • cytosol Source: Reactome
  • extracellular exosome Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm

Pathology & Biotechi

Involvement in diseasei

Cytosolic phosphoenolpyruvate carboxykinase deficiency (C-PEPCKD)
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionMetabolic disorder resulting from impaired gluconeogenesis. It is a rare disease with less than 10 cases reported in the literature. Clinical characteristics include hypotonia, hepatomegaly, failure to thrive, lactic acidosis and hypoglycemia. Autopsy reveals fatty infiltration of both the liver and kidneys. The disorder is transmitted as an autosomal recessive trait.
See also OMIM:261680

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi70K → R: Abolishes acetylation and increases protein stability; when associated with R-71 and R-594. 1 Publication1
Mutagenesisi71K → R: Abolishes acetylation and increases protein stability; when associated with R-70 and R-594. 1 Publication1
Mutagenesisi594K → R: Abolishes acetylation and increases protein stability; when associated with R-70 and R-71. 1 Publication1

Organism-specific databases

DisGeNETi5105.
MalaCardsiPCK1.
MIMi261680. phenotype.
OpenTargetsiENSG00000124253.
Orphaneti79316. Phosphoenolpyruvate carboxykinase 1 deficiency.
PharmGKBiPA33069.

Chemistry databases

ChEMBLiCHEMBL2911.

Polymorphism and mutation databases

BioMutaiPCK1.
DMDMi93138710.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00001036271 – 622Phosphoenolpyruvate carboxykinase, cytosolic [GTP]Add BLAST622

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei19PhosphoserineCombined sources1
Modified residuei70N6-acetyllysine; by p300/EP3002 Publications1
Modified residuei71N6-acetyllysine; by p300/EP3002 Publications1
Modified residuei118PhosphoserineBy similarity1
Modified residuei178PhosphothreonineBy similarity1
Modified residuei286PhosphoserineBy similarity1
Modified residuei594N6-acetyllysine; by p300/EP3002 Publications1

Post-translational modificationi

Lysine acetylation by p300/EP300 is increased on high glucose conditions and promotes ubiquitination by UBR5, acetylation is enhanced in the presence of BAG6. Deacetylated by SIRT2.2 Publications
Ubiquitination by UBR5 leads to proteasomal degradation.1 Publication

Keywords - PTMi

Acetylation, Phosphoprotein, Ubl conjugation

Proteomic databases

EPDiP35558.
MaxQBiP35558.
PaxDbiP35558.
PeptideAtlasiP35558.
PRIDEiP35558.

PTM databases

iPTMnetiP35558.
PhosphoSitePlusiP35558.

Expressioni

Tissue specificityi

Major sites of expression are liver, kidney and adipocytes.

Inductioni

Regulated by cAMP and insulin.1 Publication

Gene expression databases

BgeeiENSG00000124253.
CleanExiHS_PCK1.
GenevisibleiP35558. HS.

Organism-specific databases

HPAiCAB017027.
HPA006277.
HPA006507.

Interactioni

Subunit structurei

Monomer.2 Publications

Protein-protein interaction databases

BioGridi111136. 76 interactors.
IntActiP35558. 2 interactors.
MINTiMINT-3013923.
STRINGi9606.ENSP00000319814.

Chemistry databases

BindingDBiP35558.

Structurei

Secondary structure

1622
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi11 – 14Combined sources4
Beta strandi15 – 18Combined sources4
Helixi20 – 22Combined sources3
Helixi25 – 38Combined sources14
Beta strandi41 – 45Combined sources5
Helixi50 – 62Combined sources13
Beta strandi65 – 68Combined sources4
Beta strandi72 – 74Combined sources3
Beta strandi76 – 78Combined sources3
Beta strandi84 – 86Combined sources3
Helixi89 – 91Combined sources3
Beta strandi92 – 95Combined sources4
Helixi99 – 102Combined sources4
Beta strandi107 – 109Combined sources3
Helixi119 – 129Combined sources11
Turni131 – 136Combined sources6
Beta strandi137 – 150Combined sources14
Beta strandi155 – 162Combined sources8
Helixi164 – 173Combined sources10
Beta strandi174 – 177Combined sources4
Helixi178 – 184Combined sources7
Beta strandi190 – 195Combined sources6
Helixi214 – 216Combined sources3
Beta strandi218 – 222Combined sources5
Helixi223 – 225Combined sources3
Beta strandi227 – 232Combined sources6
Helixi236 – 239Combined sources4
Helixi242 – 248Combined sources7
Helixi249 – 258Combined sources10
Beta strandi261 – 264Combined sources4
Beta strandi266 – 271Combined sources6
Beta strandi277 – 283Combined sources7
Helixi290 – 294Combined sources5
Beta strandi304 – 311Combined sources8
Beta strandi313 – 317Combined sources5
Beta strandi321 – 326Combined sources6
Beta strandi330 – 335Combined sources6
Turni341 – 343Combined sources3
Helixi345 – 350Combined sources6
Beta strandi356 – 359Combined sources4
Beta strandi361 – 363Combined sources3
Beta strandi388 – 391Combined sources4
Beta strandi395 – 397Combined sources3
Beta strandi405 – 409Combined sources5
Helixi410 – 412Combined sources3
Turni418 – 421Combined sources4
Beta strandi426 – 434Combined sources9
Beta strandi438 – 440Combined sources3
Beta strandi443 – 446Combined sources4
Helixi450 – 458Combined sources9
Beta strandi461 – 463Combined sources3
Beta strandi475 – 477Combined sources3
Helixi479 – 481Combined sources3
Turni483 – 485Combined sources3
Helixi490 – 499Combined sources10
Helixi500 – 502Combined sources3
Beta strandi510 – 514Combined sources5
Beta strandi525 – 527Combined sources3
Helixi530 – 533Combined sources4
Helixi534 – 544Combined sources11
Beta strandi550 – 553Combined sources4
Beta strandi556 – 559Combined sources4
Turni561 – 563Combined sources3
Helixi574 – 577Combined sources4
Helixi582 – 600Combined sources19
Helixi601 – 603Combined sources3
Helixi606 – 620Combined sources15

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1KHBX-ray1.85A1-622[»]
1KHEX-ray2.40A1-622[»]
1KHFX-ray2.02A1-622[»]
1KHGX-ray2.34A1-622[»]
1M51X-ray2.25A1-622[»]
1NHXX-ray2.10A1-622[»]
2GMVX-ray2.30A/B1-622[»]
ProteinModelPortaliP35558.
SMRiP35558.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP35558.

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni235 – 237Substrate binding3 Publications3
Regioni403 – 405Substrate binding3 Publications3

Sequence similaritiesi

Phylogenomic databases

eggNOGiKOG3749. Eukaryota.
COG1274. LUCA.
GeneTreeiENSGT00390000001912.
HOGENOMiHOG000191700.
HOVERGENiHBG053651.
InParanoidiP35558.
KOiK01596.
OMAiWLSMAQH.
OrthoDBiEOG091G02YK.
PhylomeDBiP35558.
TreeFamiTF314402.

Family and domain databases

Gene3Di3.40.449.10. 1 hit.
3.90.228.20. 2 hits.
HAMAPiMF_00452. PEPCK_GTP. 1 hit.
InterProiIPR018091. PEP_carboxykin_GTP_CS.
IPR013035. PEP_carboxykinase_C.
IPR008209. PEP_carboxykinase_GTP.
IPR008210. PEP_carboxykinase_N.
[Graphical view]
PANTHERiPTHR11561. PTHR11561. 1 hit.
PfamiPF00821. PEPCK. 1 hit.
[Graphical view]
PIRSFiPIRSF001348. PEP_carboxykinase_GTP. 1 hit.
SUPFAMiSSF68923. SSF68923. 1 hit.
PROSITEiPS00505. PEPCK_GTP. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: P35558-1) [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
MPPQLQNGLN LSAKVVQGSL DSLPQAVREF LENNAELCQP DHIHICDGSE
60 70 80 90 100
EENGRLLGQM EEEGILRRLK KYDNCWLALT DPRDVARIES KTVIVTQEQR
110 120 130 140 150
DTVPIPKTGL SQLGRWMSEE DFEKAFNARF PGCMKGRTMY VIPFSMGPLG
160 170 180 190 200
SPLSKIGIEL TDSPYVVASM RIMTRMGTPV LEAVGDGEFV KCLHSVGCPL
210 220 230 240 250
PLQKPLVNNW PCNPELTLIA HLPDRREIIS FGSGYGGNSL LGKKCFALRM
260 270 280 290 300
ASRLAKEEGW LAEHMLILGI TNPEGEKKYL AAAFPSACGK TNLAMMNPSL
310 320 330 340 350
PGWKVECVGD DIAWMKFDAQ GHLRAINPEN GFFGVAPGTS VKTNPNAIKT
360 370 380 390 400
IQKNTIFTNV AETSDGGVYW EGIDEPLASG VTITSWKNKE WSSEDGEPCA
410 420 430 440 450
HPNSRFCTPA SQCPIIDAAW ESPEGVPIEG IIFGGRRPAG VPLVYEALSW
460 470 480 490 500
QHGVFVGAAM RSEATAAAEH KGKIIMHDPF AMRPFFGYNF GKYLAHWLSM
510 520 530 540 550
AQHPAAKLPK IFHVNWFRKD KEGKFLWPGF GENSRVLEWM FNRIDGKAST
560 570 580 590 600
KLTPIGYIPK EDALNLKGLG HINMMELFSI SKEFWEKEVE DIEKYLEDQV
610 620
NADLPCEIER EILALKQRIS QM
Length:622
Mass (Da):69,195
Last modified:March 7, 2006 - v3
Checksum:i78D309E0845CC181
GO
Isoform 2 (identifier: P35558-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-3: MPP → MTT
     4-320: Missing.

Note: No experimental confirmation available.
Show »
Length:305
Mass (Da):34,156
Checksum:i2FDE6275A0F15D6C
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti250M → N in AAA02558 (PubMed:8325643).Curated1
Sequence conflicti256K → E in AAA60084 (PubMed:8490617).Curated1
Sequence conflicti291T → S in AAA02558 (PubMed:8325643).Curated1
Sequence conflicti551 – 552KL → NV in AAA60084 (PubMed:8490617).Curated2
Sequence conflicti597E → V in AAA60084 (PubMed:8490617).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_02107255R → Q.1 PublicationCorresponds to variant rs28383585dbSNPEnsembl.1
Natural variantiVAR_02107360M → T.1 PublicationCorresponds to variant rs28383586dbSNPEnsembl.1
Natural variantiVAR_021074138T → I.1 PublicationCorresponds to variant rs28359542dbSNPEnsembl.1
Natural variantiVAR_021075184V → L.5 PublicationsCorresponds to variant rs707555dbSNPEnsembl.1
Natural variantiVAR_015575267I → V.2 PublicationsCorresponds to variant rs8192708dbSNPEnsembl.1
Natural variantiVAR_021076276E → K.1 PublicationCorresponds to variant rs11552145dbSNPEnsembl.1
Natural variantiVAR_021077368V → I.1 PublicationCorresponds to variant rs1804160dbSNPEnsembl.1
Natural variantiVAR_021078427P → S.1 PublicationCorresponds to variant rs28359550dbSNPEnsembl.1
Natural variantiVAR_042444586E → D.1 PublicationCorresponds to variant rs1042529dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0570731 – 3MPP → MTT in isoform 2. 1 Publication3
Alternative sequenceiVSP_0570744 – 320Missing in isoform 2. 1 PublicationAdd BLAST317

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L05144 mRNA. Translation: AAA60084.1.
L12760 Genomic DNA. Translation: AAA02558.1.
AY794987 Genomic DNA. Translation: AAV50001.1.
AK290802 mRNA. Translation: BAF83491.1.
AK300072 mRNA. Translation: BAG61876.1.
AL035541 Genomic DNA. Translation: CAB55863.1.
CH471077 Genomic DNA. Translation: EAW75514.1.
BC023978 mRNA. Translation: AAH23978.1.
U31519 Genomic DNA. Translation: AAA91026.1.
CCDSiCCDS13460.1. [P35558-1]
PIRiA45746.
RefSeqiNP_002582.3. NM_002591.3. [P35558-1]
UniGeneiHs.1872.

Genome annotation databases

EnsembliENST00000319441; ENSP00000319814; ENSG00000124253. [P35558-1]
GeneIDi5105.
KEGGihsa:5105.
UCSCiuc002xyn.5. human. [P35558-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Web resourcesi

NIEHS-SNPs

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L05144 mRNA. Translation: AAA60084.1.
L12760 Genomic DNA. Translation: AAA02558.1.
AY794987 Genomic DNA. Translation: AAV50001.1.
AK290802 mRNA. Translation: BAF83491.1.
AK300072 mRNA. Translation: BAG61876.1.
AL035541 Genomic DNA. Translation: CAB55863.1.
CH471077 Genomic DNA. Translation: EAW75514.1.
BC023978 mRNA. Translation: AAH23978.1.
U31519 Genomic DNA. Translation: AAA91026.1.
CCDSiCCDS13460.1. [P35558-1]
PIRiA45746.
RefSeqiNP_002582.3. NM_002591.3. [P35558-1]
UniGeneiHs.1872.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1KHBX-ray1.85A1-622[»]
1KHEX-ray2.40A1-622[»]
1KHFX-ray2.02A1-622[»]
1KHGX-ray2.34A1-622[»]
1M51X-ray2.25A1-622[»]
1NHXX-ray2.10A1-622[»]
2GMVX-ray2.30A/B1-622[»]
ProteinModelPortaliP35558.
SMRiP35558.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi111136. 76 interactors.
IntActiP35558. 2 interactors.
MINTiMINT-3013923.
STRINGi9606.ENSP00000319814.

Chemistry databases

BindingDBiP35558.
ChEMBLiCHEMBL2911.

PTM databases

iPTMnetiP35558.
PhosphoSitePlusiP35558.

Polymorphism and mutation databases

BioMutaiPCK1.
DMDMi93138710.

Proteomic databases

EPDiP35558.
MaxQBiP35558.
PaxDbiP35558.
PeptideAtlasiP35558.
PRIDEiP35558.

Protocols and materials databases

DNASUi5105.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000319441; ENSP00000319814; ENSG00000124253. [P35558-1]
GeneIDi5105.
KEGGihsa:5105.
UCSCiuc002xyn.5. human. [P35558-1]

Organism-specific databases

CTDi5105.
DisGeNETi5105.
GeneCardsiPCK1.
H-InvDBHIX0015941.
HGNCiHGNC:8724. PCK1.
HPAiCAB017027.
HPA006277.
HPA006507.
MalaCardsiPCK1.
MIMi261680. phenotype.
614168. gene.
neXtProtiNX_P35558.
OpenTargetsiENSG00000124253.
Orphaneti79316. Phosphoenolpyruvate carboxykinase 1 deficiency.
PharmGKBiPA33069.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG3749. Eukaryota.
COG1274. LUCA.
GeneTreeiENSGT00390000001912.
HOGENOMiHOG000191700.
HOVERGENiHBG053651.
InParanoidiP35558.
KOiK01596.
OMAiWLSMAQH.
OrthoDBiEOG091G02YK.
PhylomeDBiP35558.
TreeFamiTF314402.

Enzyme and pathway databases

UniPathwayiUPA00138.
BioCyciMetaCyc:HS04751-MONOMER.
ZFISH:HS04751-MONOMER.
BRENDAi4.1.1.32. 2681.
ReactomeiR-HSA-2161541. Abacavir metabolism.
R-HSA-381340. Transcriptional regulation of white adipocyte differentiation.
R-HSA-70263. Gluconeogenesis.
SABIO-RKP35558.
SIGNORiP35558.

Miscellaneous databases

ChiTaRSiPCK1. human.
EvolutionaryTraceiP35558.
GeneWikiiPCK1.
GenomeRNAii5105.
PROiP35558.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000124253.
CleanExiHS_PCK1.
GenevisibleiP35558. HS.

Family and domain databases

Gene3Di3.40.449.10. 1 hit.
3.90.228.20. 2 hits.
HAMAPiMF_00452. PEPCK_GTP. 1 hit.
InterProiIPR018091. PEP_carboxykin_GTP_CS.
IPR013035. PEP_carboxykinase_C.
IPR008209. PEP_carboxykinase_GTP.
IPR008210. PEP_carboxykinase_N.
[Graphical view]
PANTHERiPTHR11561. PTHR11561. 1 hit.
PfamiPF00821. PEPCK. 1 hit.
[Graphical view]
PIRSFiPIRSF001348. PEP_carboxykinase_GTP. 1 hit.
SUPFAMiSSF68923. SSF68923. 1 hit.
PROSITEiPS00505. PEPCK_GTP. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPCKGC_HUMAN
AccessioniPrimary (citable) accession number: P35558
Secondary accession number(s): A8K437
, B4DT64, Q8TCA3, Q9UJD2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: June 1, 1994
Last sequence update: March 7, 2006
Last modified: November 2, 2016
This is version 180 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

Miscellaneous

In eukaryotes there are two isozymes: a cytoplasmic one and a mitochondrial one.

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 20
    Human chromosome 20: 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.