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Protein

High affinity cAMP-specific and IBMX-insensitive 3',5'-cyclic phosphodiesterase 8B

Gene

PDE8B

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

Functioni

Hydrolyzes the second messenger cAMP, which is a key regulator of many important physiological processes. May be involved in specific signaling in the thyroid gland.

Catalytic activityi

Adenosine 3',5'-cyclic phosphate + H2O = adenosine 5'-phosphate.1 Publication

Cofactori

a divalent metal cationBy similarityNote: Binds 2 divalent metal cations per subunit. Site 1 may preferentially bind zinc ions, while site 2 has a preference for magnesium and/or manganese ions.By similarity

Enzyme regulationi

Inhibited by dipyridimole. Insensitive to selective PDE inhibitors including rolipram and milrinone as well as to the non-selective inhibitor, IBMX. Unaffected by cGMP.1 Publication

Pathwayi: 3',5'-cyclic AMP degradation

This protein is involved in step 1 of the subpathway that synthesizes AMP from 3',5'-cyclic AMP.
Proteins known to be involved in this subpathway in this organism are:
  1. cAMP-specific 3',5'-cyclic phosphodiesterase 4C (PDE4C), cAMP and cAMP-inhibited cGMP 3',5'-cyclic phosphodiesterase 10A (PDE10A), cAMP-specific 3',5'-cyclic phosphodiesterase 4A (PDE4A), High affinity cAMP-specific 3',5'-cyclic phosphodiesterase 7A (PDE7A), cAMP-specific 3',5'-cyclic phosphodiesterase 7B (PDE7B), cAMP-specific 3',5'-cyclic phosphodiesterase 4D (PDE4D), cAMP-specific 3',5'-cyclic phosphodiesterase 4B (PDE4B), High affinity cAMP-specific and IBMX-insensitive 3',5'-cyclic phosphodiesterase 8B (PDE8B), High affinity cAMP-specific and IBMX-insensitive 3',5'-cyclic phosphodiesterase 8A (PDE8A)
This subpathway is part of the pathway 3',5'-cyclic AMP degradation, which is itself part of Purine metabolism.
View all proteins of this organism that are known to be involved in the subpathway that synthesizes AMP from 3',5'-cyclic AMP, the pathway 3',5'-cyclic AMP degradation and in Purine metabolism.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Active sitei615Proton donorBy similarity1
Metal bindingi619Divalent metal cation 1By similarity1
Metal bindingi655Divalent metal cation 1By similarity1
Metal bindingi656Divalent metal cation 1By similarity1
Metal bindingi656Divalent metal cation 2By similarity1
Metal bindingi781Divalent metal cation 1By similarity1

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Hydrolase

Keywords - Ligandi

cAMP, Metal-binding

Enzyme and pathway databases

BioCyciZFISH:HS03659-MONOMER.
BRENDAi3.1.4.53. 2681.
ReactomeiR-HSA-418555. G alpha (s) signalling events.
UniPathwayiUPA00762; UER00747.

Names & Taxonomyi

Protein namesi
Recommended name:
High affinity cAMP-specific and IBMX-insensitive 3',5'-cyclic phosphodiesterase 8B (EC:3.1.4.53)
Short name:
HsPDE8B
Alternative name(s):
Cell proliferation-inducing gene 22 protein
Gene namesi
Name:PDE8B
ORF Names:PIG22
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 5

Organism-specific databases

HGNCiHGNC:8794. PDE8B.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Pathology & Biotechi

Involvement in diseasei

Striatal degeneration, autosomal dominant 1 (ADSD1)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA movement disorder affecting the striatal part of the basal ganglia and characterized by bradykinesia, dysarthria and muscle rigidity. These symptoms resemble idiopathic Parkinson disease, but tremor is not present.
See also OMIM:609161
Primary pigmented nodular adrenocortical disease 3 (PPNAD3)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA rare bilateral adrenal defect causing ACTH-independent Cushing syndrome. Macroscopic appearance of the adrenals is characteristic with small pigmented micronodules observed in the cortex. Adrenal glands show overall normal size and weight, and multiple small yellow-to-dark brown nodules surrounded by a cortex with a uniform appearance. Microscopically, there are moderate diffuse cortical hyperplasia with mostly nonpigmented nodules, multiple capsular deficits and massive circumscribed and infiltrating extra-adrenal cortical excrescences with micronodules. Clinical manifestations of Cushing syndrome include facial and truncal obesity, abdominal striae, muscular weakness, osteoporosis, arterial hypertension, diabetes.
See also OMIM:614190
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_066503305H → P in PPNAD3; shows significantly higher cyclic AMP levels after transfection with the mutant protein than after transfection with the wild-type, indicating an impaired ability of the mutant protein to degrade cAMP. 1 PublicationCorresponds to variant rs121918360dbSNPEnsembl.1

Keywords - Diseasei

Cushing syndrome, Disease mutation

Organism-specific databases

DisGeNETi8622.
MalaCardsiPDE8B.
MIMi609161. phenotype.
614190. phenotype.
OpenTargetsiENSG00000113231.
Orphaneti228169. Autosomal dominant striatal neurodegeneration.
189439. Primary pigmented nodular adrenocortical disease.
PharmGKBiPA33142.

Chemistry databases

ChEMBLiCHEMBL4408.
DrugBankiDB00201. Caffeine.
DB00920. Ketotifen.
GuidetoPHARMACOLOGYi1308.

Polymorphism and mutation databases

BioMutaiPDE8B.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00001988401 – 885High affinity cAMP-specific and IBMX-insensitive 3',5'-cyclic phosphodiesterase 8BAdd BLAST885

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei517PhosphoserineCombined sources1
Modified residuei754PhosphoserineBy similarity1

Keywords - PTMi

Phosphoprotein

Proteomic databases

MaxQBiO95263.
PaxDbiO95263.
PeptideAtlasiO95263.
PRIDEiO95263.

2D gel databases

UCD-2DPAGEO95263.

PTM databases

iPTMnetiO95263.
PhosphoSitePlusiO95263.

Expressioni

Tissue specificityi

Abundantly expressed in the thyroid. Also very weakly expressed in brain, spinal cord and placenta. In the thyroid isoform 1 predominates, and isoforms 2 and 6 are also highly expressed. In the placenta isoforms 1 and 2 are expressed equally. In the brain isoform 2 predominates.2 Publications

Gene expression databases

BgeeiENSG00000113231.
CleanExiHS_PDE8B.
ExpressionAtlasiO95263. baseline and differential.
GenevisibleiO95263. HS.

Organism-specific databases

HPAiHPA036912.

Interactioni

Protein-protein interaction databases

BioGridi114177. 1 interactor.
IntActiO95263. 1 interactor.
STRINGi9606.ENSP00000264917.

Chemistry databases

BindingDBiO95263.

Structurei

3D structure databases

ProteinModelPortaliO95263.
SMRiO95263.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini267 – 338PASPROSITE-ProRule annotationAdd BLAST72

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni590 – 868CatalyticBy similarityAdd BLAST279

Domaini

Composed of a C-terminal catalytic domain containing two putative divalent metal sites and an N-terminal regulatory domain.

Sequence similaritiesi

Contains 1 PAS (PER-ARNT-SIM) domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiKOG1229. Eukaryota.
ENOG410XP9B. LUCA.
GeneTreeiENSGT00760000118889.
HOVERGENiHBG053544.
KOiK18437.
OMAiDHRQTQN.
OrthoDBiEOG091G0337.
PhylomeDBiO95263.
TreeFamiTF314638.

Family and domain databases

Gene3Di1.10.1300.10. 1 hit.
InterProiIPR003607. HD/PDEase_dom.
IPR000014. PAS.
IPR023088. PDEase.
IPR002073. PDEase_catalytic_dom.
IPR023174. PDEase_CS.
IPR013938. PDEase_PDE8.
[Graphical view]
PfamiPF13426. PAS_9. 1 hit.
PF08629. PDE8. 1 hit.
PF00233. PDEase_I. 1 hit.
[Graphical view]
PRINTSiPR00387. PDIESTERASE1.
SMARTiSM00471. HDc. 1 hit.
SM00091. PAS. 1 hit.
[Graphical view]
SUPFAMiSSF55785. SSF55785. 1 hit.
TIGRFAMsiTIGR00229. sensory_box. 1 hit.
PROSITEiPS50112. PAS. 1 hit.
PS00126. PDEASE_I. 1 hit.
[Graphical view]

Sequences (6)i

Sequence statusi: Complete.

This entry describes 6 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: O95263-1) [UniParc]FASTAAdd to basket
Also known as: PDE8B1

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
MGCAPSIHVS QSGVIYCRDS DESSSPRQTT SVSQGPAAPL PGLFVQTDAA
60 70 80 90 100
DAIPPSRASG PPSVARVRRA RTELGSGSSA GSAAPAATTS RGRRRHCCSS
110 120 130 140 150
AEAETQTCYT SVKQVSSAEV RIGPMRLTQD PIQVLLIFAK EDSQSDGFWW
160 170 180 190 200
ACDRAGYRCN IARTPESALE CFLDKHHEII VIDHRQTQNF DAEAVCRSIR
210 220 230 240 250
ATNPSEHTVI LAVVSRVSDD HEEASVLPLL HAGFNRRFME NSSIIACYNE
260 270 280 290 300
LIQIEHGEVR SQFKLRACNS VFTALDHCHE AIEITSDDHV IQYVNPAFER
310 320 330 340 350
MMGYHKGELL GKELADLPKS DKNRADLLDT INTCIKKGKE WQGVYYARRK
360 370 380 390 400
SGDSIQQHVK ITPVIGQGGK IRHFVSLKKL CCTTDNNKQI HKIHRDSGDN
410 420 430 440 450
SQTEPHSFRY KNRRKESIDV KSISSRGSDA PSLQNRRYPS MARIHSMTIE
460 470 480 490 500
APITKVINII NAAQENSPVT VAEALDRVLE ILRTTELYSP QLGTKDEDPH
510 520 530 540 550
TSDLVGGLMT DGLRRLSGNE YVFTKNVHQS HSHLAMPITI NDVPPCISQL
560 570 580 590 600
LDNEESWDFN IFELEAITHK RPLVYLGLKV FSRFGVCEFL NCSETTLRAW
610 620 630 640 650
FQVIEANYHS SNAYHNSTHA ADVLHATAFF LGKERVKGSL DQLDEVAALI
660 670 680 690 700
AATVHDVDHP GRTNSFLCNA GSELAVLYND TAVLESHHTA LAFQLTVKDT
710 720 730 740 750
KCNIFKNIDR NHYRTLRQAI IDMVLATEMT KHFEHVNKFV NSINKPMAAE
760 770 780 790 800
IEGSDCECNP AGKNFPENQI LIKRMMIKCA DVANPCRPLD LCIEWAGRIS
810 820 830 840 850
EEYFAQTDEE KRQGLPVVMP VFDRNTCSIP KSQISFIDYF ITDMFDAWDA
860 870 880
FAHLPALMQH LADNYKHWKT LDDLKCKSLR LPSDS
Note: Major isoform.
Length:885
Mass (Da):98,979
Last modified:August 22, 2003 - v2
Checksum:iDB4F763E51F745A3
GO
Isoform 2 (identifier: O95263-2) [UniParc]FASTAAdd to basket
Also known as: PDE8B2, PDE8B3

The sequence of this isoform differs from the canonical sequence as follows:
     293-389: Missing.

Show »
Length:788
Mass (Da):87,974
Checksum:i816AECACCAE45447
GO
Isoform 3 (identifier: O95263-3) [UniParc]FASTAAdd to basket
Also known as: PDE8B3

The sequence of this isoform differs from the canonical sequence as follows:
     456-510: Missing.

Show »
Length:830
Mass (Da):93,047
Checksum:i5A39ED08E2A877E4
GO
Isoform 4 (identifier: O95263-4) [UniParc]FASTAAdd to basket
Also known as: PDE8B4

The sequence of this isoform differs from the canonical sequence as follows:
     114-133: Missing.

Show »
Length:865
Mass (Da):96,771
Checksum:iDDC83E5525C7E7B7
GO
Isoform 5 (identifier: O95263-5) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-535: Missing.

Note: No experimental confirmation available.
Show »
Length:350
Mass (Da):39,791
Checksum:iA6D4F19BE26C045F
GO
Isoform 6 (identifier: O95263-6) [UniParc]FASTAAdd to basket
Also known as: PDE8B2

The sequence of this isoform differs from the canonical sequence as follows:
     293-339: Missing.

Show »
Length:838
Mass (Da):93,674
Checksum:i013C790AC0F24F92
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti147G → R in CAD38584 (PubMed:17974005).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_066503305H → P in PPNAD3; shows significantly higher cyclic AMP levels after transfection with the mutant protein than after transfection with the wild-type, indicating an impaired ability of the mutant protein to degrade cAMP. 1 PublicationCorresponds to variant rs121918360dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0080811 – 535Missing in isoform 5. 2 PublicationsAdd BLAST535
Alternative sequenceiVSP_008082114 – 133Missing in isoform 4. 1 PublicationAdd BLAST20
Alternative sequenceiVSP_008084293 – 389Missing in isoform 2. 2 PublicationsAdd BLAST97
Alternative sequenceiVSP_008083293 – 339Missing in isoform 6. 1 PublicationAdd BLAST47
Alternative sequenceiVSP_008085456 – 510Missing in isoform 3. 1 PublicationAdd BLAST55

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY129948 mRNA. Translation: AAN71723.1.
AY129949 mRNA. Translation: AAN71724.1.
AY129950 Genomic DNA. Translation: AAN71725.1.
AY129950 Genomic DNA. Translation: AAN71726.1.
AY129950 Genomic DNA. Translation: AAN71727.1.
AB085824 mRNA. Translation: BAC53762.1.
AB085825 mRNA. Translation: BAC53763.1.
AB085826 mRNA. Translation: BAC53764.1.
AB085827 mRNA. Translation: BAC53765.1.
AY423729 mRNA. Translation: AAS00492.1.
CH471084 Genomic DNA. Translation: EAW95803.1.
BC043209 mRNA. No translation available.
AF079529 mRNA. Translation: AAC69564.2.
AL831924 mRNA. Translation: CAD38584.1.
CCDSiCCDS34190.1. [O95263-3]
CCDS34191.1. [O95263-6]
CCDS34192.1. [O95263-2]
CCDS34193.1. [O95263-4]
CCDS4037.1. [O95263-1]
PIRiJE0293.
RefSeqiNP_001025022.1. NM_001029851.2. [O95263-2]
NP_001025023.1. NM_001029852.2. [O95263-3]
NP_001025024.1. NM_001029853.2. [O95263-4]
NP_001025025.1. NM_001029854.2. [O95263-6]
NP_003710.1. NM_003719.3. [O95263-1]
UniGeneiHs.584830.

Genome annotation databases

EnsembliENST00000264917; ENSP00000264917; ENSG00000113231. [O95263-1]
ENST00000333194; ENSP00000331336; ENSG00000113231. [O95263-3]
ENST00000340978; ENSP00000345446; ENSG00000113231. [O95263-6]
ENST00000342343; ENSP00000345646; ENSG00000113231. [O95263-4]
ENST00000346042; ENSP00000330428; ENSG00000113231. [O95263-2]
ENST00000505283; ENSP00000423461; ENSG00000113231. [O95263-5]
GeneIDi8622.
KEGGihsa:8622.
UCSCiuc003kfa.4. human. [O95263-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY129948 mRNA. Translation: AAN71723.1.
AY129949 mRNA. Translation: AAN71724.1.
AY129950 Genomic DNA. Translation: AAN71725.1.
AY129950 Genomic DNA. Translation: AAN71726.1.
AY129950 Genomic DNA. Translation: AAN71727.1.
AB085824 mRNA. Translation: BAC53762.1.
AB085825 mRNA. Translation: BAC53763.1.
AB085826 mRNA. Translation: BAC53764.1.
AB085827 mRNA. Translation: BAC53765.1.
AY423729 mRNA. Translation: AAS00492.1.
CH471084 Genomic DNA. Translation: EAW95803.1.
BC043209 mRNA. No translation available.
AF079529 mRNA. Translation: AAC69564.2.
AL831924 mRNA. Translation: CAD38584.1.
CCDSiCCDS34190.1. [O95263-3]
CCDS34191.1. [O95263-6]
CCDS34192.1. [O95263-2]
CCDS34193.1. [O95263-4]
CCDS4037.1. [O95263-1]
PIRiJE0293.
RefSeqiNP_001025022.1. NM_001029851.2. [O95263-2]
NP_001025023.1. NM_001029852.2. [O95263-3]
NP_001025024.1. NM_001029853.2. [O95263-4]
NP_001025025.1. NM_001029854.2. [O95263-6]
NP_003710.1. NM_003719.3. [O95263-1]
UniGeneiHs.584830.

3D structure databases

ProteinModelPortaliO95263.
SMRiO95263.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi114177. 1 interactor.
IntActiO95263. 1 interactor.
STRINGi9606.ENSP00000264917.

Chemistry databases

BindingDBiO95263.
ChEMBLiCHEMBL4408.
DrugBankiDB00201. Caffeine.
DB00920. Ketotifen.
GuidetoPHARMACOLOGYi1308.

PTM databases

iPTMnetiO95263.
PhosphoSitePlusiO95263.

Polymorphism and mutation databases

BioMutaiPDE8B.

2D gel databases

UCD-2DPAGEO95263.

Proteomic databases

MaxQBiO95263.
PaxDbiO95263.
PeptideAtlasiO95263.
PRIDEiO95263.

Protocols and materials databases

DNASUi8622.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000264917; ENSP00000264917; ENSG00000113231. [O95263-1]
ENST00000333194; ENSP00000331336; ENSG00000113231. [O95263-3]
ENST00000340978; ENSP00000345446; ENSG00000113231. [O95263-6]
ENST00000342343; ENSP00000345646; ENSG00000113231. [O95263-4]
ENST00000346042; ENSP00000330428; ENSG00000113231. [O95263-2]
ENST00000505283; ENSP00000423461; ENSG00000113231. [O95263-5]
GeneIDi8622.
KEGGihsa:8622.
UCSCiuc003kfa.4. human. [O95263-1]

Organism-specific databases

CTDi8622.
DisGeNETi8622.
GeneCardsiPDE8B.
H-InvDBHIX0004971.
HGNCiHGNC:8794. PDE8B.
HPAiHPA036912.
MalaCardsiPDE8B.
MIMi603390. gene.
609161. phenotype.
614190. phenotype.
neXtProtiNX_O95263.
OpenTargetsiENSG00000113231.
Orphaneti228169. Autosomal dominant striatal neurodegeneration.
189439. Primary pigmented nodular adrenocortical disease.
PharmGKBiPA33142.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG1229. Eukaryota.
ENOG410XP9B. LUCA.
GeneTreeiENSGT00760000118889.
HOVERGENiHBG053544.
KOiK18437.
OMAiDHRQTQN.
OrthoDBiEOG091G0337.
PhylomeDBiO95263.
TreeFamiTF314638.

Enzyme and pathway databases

UniPathwayiUPA00762; UER00747.
BioCyciZFISH:HS03659-MONOMER.
BRENDAi3.1.4.53. 2681.
ReactomeiR-HSA-418555. G alpha (s) signalling events.

Miscellaneous databases

ChiTaRSiPDE8B. human.
GeneWikiiPDE8B.
GenomeRNAii8622.
PROiO95263.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000113231.
CleanExiHS_PDE8B.
ExpressionAtlasiO95263. baseline and differential.
GenevisibleiO95263. HS.

Family and domain databases

Gene3Di1.10.1300.10. 1 hit.
InterProiIPR003607. HD/PDEase_dom.
IPR000014. PAS.
IPR023088. PDEase.
IPR002073. PDEase_catalytic_dom.
IPR023174. PDEase_CS.
IPR013938. PDEase_PDE8.
[Graphical view]
PfamiPF13426. PAS_9. 1 hit.
PF08629. PDE8. 1 hit.
PF00233. PDEase_I. 1 hit.
[Graphical view]
PRINTSiPR00387. PDIESTERASE1.
SMARTiSM00471. HDc. 1 hit.
SM00091. PAS. 1 hit.
[Graphical view]
SUPFAMiSSF55785. SSF55785. 1 hit.
TIGRFAMsiTIGR00229. sensory_box. 1 hit.
PROSITEiPS50112. PAS. 1 hit.
PS00126. PDEASE_I. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPDE8B_HUMAN
AccessioniPrimary (citable) accession number: O95263
Secondary accession number(s): Q5J7V7
, Q86XK8, Q8IUJ7, Q8IUJ8, Q8IUJ9, Q8IUK0, Q8N3T2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: May 30, 2000
Last sequence update: August 22, 2003
Last modified: November 2, 2016
This is version 167 of the entry and version 2 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

Complete proteome, Reference proteome

Documents

  1. Human chromosome 5
    Human chromosome 5: 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. 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.