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Protein

Ribosyldihydronicotinamide dehydrogenase [quinone]

Gene

NQO2

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

Functioni

The enzyme apparently serves as a quinone reductase in connection with conjugation reactions of hydroquinones involved in detoxification pathways as well as in biosynthetic processes such as the vitamin K-dependent gamma-carboxylation of glutamate residues in prothrombin synthesis.1 Publication

Catalytic activityi

1-(beta-D-ribofuranosyl)-1,4-dihydronicotinamide + a quinone = 1-(beta-D-ribofuranosyl)nicotinamide + a quinol.1 Publication

Cofactori

Protein has several cofactor binding sites:
  • Zn2+Note: Binds 1 zinc ion per subunit.
  • FAD

Enzyme regulationi

Inhibited by melatonin, resveratrol and 5-hydroxytryptamine.1 Publication

Kineticsi

  1. KM=28 µM for NRH2 Publications
  2. KM=11.6 µM for menadione2 Publications
  3. KM=252 µM for NADH2 Publications

    Sites

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Binding sitei12FAD2 Publications1
    Binding sitei156FAD2 Publications1
    Metal bindingi174Zinc1
    Metal bindingi178Zinc1
    Binding sitei194FAD2 Publications1
    Binding sitei201FAD2 Publications1
    Metal bindingi223Zinc1

    Regions

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Nucleotide bindingi18 – 21FAD2 Publications4
    Nucleotide bindingi104 – 107FAD2 Publications4
    Nucleotide bindingi148 – 151FAD2 Publications4

    GO - Molecular functioni

    • electron carrier activity Source: UniProtKB
    • metal ion binding Source: UniProtKB-KW
    • NADPH dehydrogenase (quinone) activity Source: ProtInc

    GO - Biological processi

    Complete GO annotation...

    Keywords - Molecular functioni

    Oxidoreductase

    Keywords - Ligandi

    FAD, Flavoprotein, Metal-binding, Zinc

    Enzyme and pathway databases

    BioCyciZFISH:HS04802-MONOMER.
    BRENDAi1.10.99.2. 2681.
    SABIO-RKP16083.

    Names & Taxonomyi

    Protein namesi
    Recommended name:
    Ribosyldihydronicotinamide dehydrogenase [quinone] (EC:1.10.5.11 Publication)
    Alternative name(s):
    NRH dehydrogenase [quinone] 2
    NRH:quinone oxidoreductase 2
    Quinone reductase 2
    Short name:
    QR2
    Gene namesi
    Name:NQO2
    Synonyms:NMOR2
    OrganismiHomo sapiens (Human)
    Taxonomic identifieri9606 [NCBI]
    Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
    Proteomesi
    • UP000005640 Componenti: Chromosome 6

    Organism-specific databases

    HGNCiHGNC:7856. NQO2.

    Subcellular locationi

    GO - Cellular componenti

    • cytoplasm Source: HPA
    • extracellular exosome Source: UniProtKB
    • nucleoplasm Source: HPA
    Complete GO annotation...

    Keywords - Cellular componenti

    Cytoplasm

    Pathology & Biotechi

    Mutagenesis

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Mutagenesisi162N → H: Loss of activity toward CB1954, no effect toward menadione. 1 Publication1

    Organism-specific databases

    DisGeNETi4835.
    MalaCardsiNQO2.
    OpenTargetsiENSG00000124588.
    PharmGKBiPA31745.

    Chemistry databases

    ChEMBLiCHEMBL3959.
    DrugBankiDB06695. Dabigatran etexilate.
    DB03147. Flavin adenine dinucleotide.
    DB01065. Melatonin.
    DB00170. Menadione.
    DB01087. Primaquine.

    Polymorphism and mutation databases

    BioMutaiNQO2.
    DMDMi317373581.

    PTM / Processingi

    Molecule processing

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    ChainiPRO_00000716261 – 231Ribosyldihydronicotinamide dehydrogenase [quinone]Add BLAST231

    Amino acid modifications

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Modified residuei80PhosphoserineCombined sources1
    Modified residuei197PhosphoserineCombined sources1

    Keywords - PTMi

    Phosphoprotein

    Proteomic databases

    EPDiP16083.
    MaxQBiP16083.
    PaxDbiP16083.
    PeptideAtlasiP16083.
    PRIDEiP16083.

    PTM databases

    iPTMnetiP16083.
    PhosphoSitePlusiP16083.

    Expressioni

    Gene expression databases

    BgeeiENSG00000124588.
    CleanExiHS_NQO2.
    ExpressionAtlasiP16083. baseline and differential.
    GenevisibleiP16083. HS.

    Organism-specific databases

    HPAiHPA021283.
    HPA021332.

    Interactioni

    Subunit structurei

    Homodimer.4 Publications

    Binary interactionsi

    WithEntry#Exp.IntActNotes
    GORASP2Q9H8Y83EBI-358466,EBI-739467
    LRRC7A1L1C63EBI-358466,EBI-10171988

    Protein-protein interaction databases

    BioGridi110898. 12 interactors.
    IntActiP16083. 11 interactors.
    MINTiMINT-1133243.
    STRINGi9606.ENSP00000337773.

    Chemistry databases

    BindingDBiP16083.

    Structurei

    Secondary structure

    1231
    Legend: HelixTurnBeta strandPDB Structure known for this area
    Show more details
    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Beta strandi5 – 10Combined sources6
    Helixi18 – 33Combined sources16
    Beta strandi36 – 41Combined sources6
    Turni42 – 46Combined sources5
    Helixi53 – 55Combined sources3
    Beta strandi63 – 65Combined sources3
    Helixi68 – 77Combined sources10
    Helixi83 – 94Combined sources12
    Beta strandi96 – 103Combined sources8
    Beta strandi105 – 108Combined sources4
    Helixi111 – 120Combined sources10
    Turni123 – 125Combined sources3
    Beta strandi129 – 132Combined sources4
    Helixi133 – 135Combined sources3
    Turni137 – 140Combined sources4
    Beta strandi142 – 148Combined sources7
    Turni153 – 156Combined sources4
    Beta strandi160 – 162Combined sources3
    Helixi165 – 173Combined sources9
    Helixi174 – 178Combined sources5
    Turni179 – 181Combined sources3
    Beta strandi188 – 190Combined sources3
    Turni193 – 195Combined sources3
    Helixi198 – 212Combined sources15
    Helixi213 – 217Combined sources5
    Helixi225 – 229Combined sources5

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    PDB entryMethodResolution (Å)ChainPositionsPDBsum
    1QR2X-ray2.10A/B2-231[»]
    1SG0X-ray1.50A/B2-231[»]
    1XI2X-ray1.50A/B2-231[»]
    1ZX1X-ray2.16A/B1-231[»]
    2BZSX-ray2.00A/B2-231[»]
    2QMYX-ray2.50A/B2-231[»]
    2QMZX-ray2.10A/B2-231[»]
    2QR2X-ray2.45A/B2-231[»]
    2QWXX-ray1.50A/B1-231[»]
    2QX4X-ray1.65A/B2-231[»]
    2QX6X-ray1.75A/B2-231[»]
    2QX8X-ray1.60A/B2-231[»]
    2QX9X-ray2.31A/B2-231[»]
    3FW1X-ray1.75A1-231[»]
    3G5MX-ray1.84A/B1-231[»]
    3GAMX-ray1.98A/B1-231[»]
    3NFRX-ray1.57A/B2-231[»]
    3NHFX-ray2.00A/B2-231[»]
    3NHJX-ray2.33A/B2-231[»]
    3NHKX-ray1.96A/B2-231[»]
    3NHLX-ray1.57A/B2-231[»]
    3NHPX-ray1.70A/B2-231[»]
    3NHRX-ray1.80A/B2-231[»]
    3NHSX-ray1.78A/B2-231[»]
    3NHUX-ray1.90A/B2-231[»]
    3NHWX-ray1.65A/B2-231[»]
    3NHYX-ray1.90A/B2-231[»]
    3O2NX-ray1.60A/B2-231[»]
    3O73X-ray2.00A/B1-231[»]
    3OVMX-ray2.09A/B1-231[»]
    3OWHX-ray2.28A/B1-231[»]
    3OWXX-ray1.85A/B1-231[»]
    3OX1X-ray2.00A/B1-231[»]
    3OX2X-ray2.41A/B1-231[»]
    3OX3X-ray1.80A/B1-231[»]
    3TE7X-ray1.70A/B3-230[»]
    3TEMX-ray1.45A/B3-230[»]
    3TZBX-ray2.19A/B/C/D3-230[»]
    3UXEX-ray1.50A/B2-231[»]
    3UXHX-ray1.53A/B2-231[»]
    4FGJX-ray1.35A/B1-231[»]
    4FGKX-ray1.40A/B1-231[»]
    4FGLX-ray1.20A/B/C/D1-231[»]
    4GQIX-ray1.95A/B2-231[»]
    4GR9X-ray2.29A/B2-231[»]
    4QODX-ray1.35A/B1-231[»]
    4QOEX-ray1.45A/B1-231[»]
    4QOFX-ray1.55A/B1-231[»]
    4QOGX-ray1.40A/B1-231[»]
    4QOHX-ray1.60A/B1-231[»]
    4QOIX-ray1.55A/B1-231[»]
    4QOJX-ray1.85A/B1-231[»]
    4U7FX-ray1.80A/B2-231[»]
    4U7GX-ray1.96A/B2-231[»]
    4U7HX-ray1.48A/B2-231[»]
    4XDGX-ray1.50A/B1-231[»]
    4XDHX-ray1.90A/B1-231[»]
    4ZVKX-ray1.87A/B2-231[»]
    4ZVLX-ray1.90A/B2-231[»]
    4ZVMX-ray1.97A/B2-231[»]
    4ZVNX-ray1.87A/B2-231[»]
    5BUCX-ray1.87A/B2-231[»]
    5LBTX-ray1.75A/B1-231[»]
    5LBUX-ray1.65A/B1-231[»]
    DisProtiDP00727.
    ProteinModelPortaliP16083.
    SMRiP16083.
    ModBaseiSearch...
    MobiDBiSearch...

    Miscellaneous databases

    EvolutionaryTraceiP16083.

    Family & Domainsi

    Region

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Regioni127 – 129Substrate binding3

    Sequence similaritiesi

    Phylogenomic databases

    eggNOGiENOG410IKWF. Eukaryota.
    COG2249. LUCA.
    GeneTreeiENSGT00440000033410.
    HOGENOMiHOG000149970.
    HOVERGENiHBG029104.
    InParanoidiP16083.
    KOiK08071.
    OMAiRLQTIWK.
    OrthoDBiEOG091G183R.
    PhylomeDBiP16083.
    TreeFamiTF300296.

    Family and domain databases

    Gene3Di3.40.50.360. 1 hit.
    InterProiIPR003680. Flavodoxin_fold.
    IPR029039. Flavoprotein-like_dom.
    [Graphical view]
    PfamiPF02525. Flavodoxin_2. 1 hit.
    [Graphical view]
    SUPFAMiSSF52218. SSF52218. 1 hit.

    Sequencei

    Sequence statusi: Complete.

    P16083-1 [UniParc]FASTAAdd to basket

    « Hide

            10         20         30         40         50
    MAGKKVLIVY AHQEPKSFNG SLKNVAVDEL SRQGCTVTVS DLYAMNLEPR
    60 70 80 90 100
    ATDKDITGTL SNPEVFNYGV ETHEAYKQRS LASDITDEQK KVREADLVIF
    110 120 130 140 150
    QFPLYWFSVP AILKGWMDRV LCQGFAFDIP GFYDSGLLQG KLALLSVTTG
    160 170 180 190 200
    GTAEMYTKTG VNGDSRYFLW PLQHGTLHFC GFKVLAPQIS FAPEIASEEE
    210 220 230
    RKGMVAAWSQ RLQTIWKEEP IPCTAHWHFG Q
    Length:231
    Mass (Da):25,919
    Last modified:January 11, 2011 - v5
    Checksum:iFE1F4D577517B972
    GO

    Experimental Info

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Sequence conflicti140G → C in AAB60642 (PubMed:8182056).Curated1

    Natural variant

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Natural variantiVAR_02139916K → R.1 PublicationCorresponds to variant rs28383623dbSNPEnsembl.1
    Natural variantiVAR_02140029E → G.1 PublicationCorresponds to variant rs17136117dbSNPEnsembl.1
    Natural variantiVAR_02140147L → F.7 PublicationsCorresponds to variant rs1143684dbSNPEnsembl.1
    Natural variantiVAR_02140258G → D.1 PublicationCorresponds to variant rs17300141dbSNPEnsembl.1
    Natural variantiVAR_021403184V → A.1 PublicationCorresponds to variant rs28383651dbSNPEnsembl.1

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    J02888 mRNA. Translation: AAA60239.1.
    AY299456 Genomic DNA. Translation: AAB60642.3.
    AB050248 Genomic DNA. Translation: BAB16974.1.
    AY855291 Genomic DNA. Translation: AAW29945.1.
    AK311746 mRNA. Translation: BAG34689.1.
    AL133351 Genomic DNA. Translation: CAI23294.1.
    CH471087 Genomic DNA. Translation: EAW55107.1.
    BC006096 mRNA. Translation: AAH06096.1.
    CCDSiCCDS4481.1.
    PIRiA32667.
    RefSeqiNP_000895.2. NM_000904.4.
    NP_001277150.1. NM_001290221.1.
    NP_001305869.1. NM_001318940.1.
    UniGeneiHs.533050.

    Genome annotation databases

    EnsembliENST00000338130; ENSP00000337773; ENSG00000124588.
    ENST00000380430; ENSP00000369795; ENSG00000124588.
    ENST00000380455; ENSP00000369822; ENSG00000124588.
    GeneIDi4835.
    KEGGihsa:4835.
    UCSCiuc003mus.3. human.

    Keywords - Coding sequence diversityi

    Polymorphism

    Cross-referencesi

    Web resourcesi

    NIEHS-SNPs

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    J02888 mRNA. Translation: AAA60239.1.
    AY299456 Genomic DNA. Translation: AAB60642.3.
    AB050248 Genomic DNA. Translation: BAB16974.1.
    AY855291 Genomic DNA. Translation: AAW29945.1.
    AK311746 mRNA. Translation: BAG34689.1.
    AL133351 Genomic DNA. Translation: CAI23294.1.
    CH471087 Genomic DNA. Translation: EAW55107.1.
    BC006096 mRNA. Translation: AAH06096.1.
    CCDSiCCDS4481.1.
    PIRiA32667.
    RefSeqiNP_000895.2. NM_000904.4.
    NP_001277150.1. NM_001290221.1.
    NP_001305869.1. NM_001318940.1.
    UniGeneiHs.533050.

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    PDB entryMethodResolution (Å)ChainPositionsPDBsum
    1QR2X-ray2.10A/B2-231[»]
    1SG0X-ray1.50A/B2-231[»]
    1XI2X-ray1.50A/B2-231[»]
    1ZX1X-ray2.16A/B1-231[»]
    2BZSX-ray2.00A/B2-231[»]
    2QMYX-ray2.50A/B2-231[»]
    2QMZX-ray2.10A/B2-231[»]
    2QR2X-ray2.45A/B2-231[»]
    2QWXX-ray1.50A/B1-231[»]
    2QX4X-ray1.65A/B2-231[»]
    2QX6X-ray1.75A/B2-231[»]
    2QX8X-ray1.60A/B2-231[»]
    2QX9X-ray2.31A/B2-231[»]
    3FW1X-ray1.75A1-231[»]
    3G5MX-ray1.84A/B1-231[»]
    3GAMX-ray1.98A/B1-231[»]
    3NFRX-ray1.57A/B2-231[»]
    3NHFX-ray2.00A/B2-231[»]
    3NHJX-ray2.33A/B2-231[»]
    3NHKX-ray1.96A/B2-231[»]
    3NHLX-ray1.57A/B2-231[»]
    3NHPX-ray1.70A/B2-231[»]
    3NHRX-ray1.80A/B2-231[»]
    3NHSX-ray1.78A/B2-231[»]
    3NHUX-ray1.90A/B2-231[»]
    3NHWX-ray1.65A/B2-231[»]
    3NHYX-ray1.90A/B2-231[»]
    3O2NX-ray1.60A/B2-231[»]
    3O73X-ray2.00A/B1-231[»]
    3OVMX-ray2.09A/B1-231[»]
    3OWHX-ray2.28A/B1-231[»]
    3OWXX-ray1.85A/B1-231[»]
    3OX1X-ray2.00A/B1-231[»]
    3OX2X-ray2.41A/B1-231[»]
    3OX3X-ray1.80A/B1-231[»]
    3TE7X-ray1.70A/B3-230[»]
    3TEMX-ray1.45A/B3-230[»]
    3TZBX-ray2.19A/B/C/D3-230[»]
    3UXEX-ray1.50A/B2-231[»]
    3UXHX-ray1.53A/B2-231[»]
    4FGJX-ray1.35A/B1-231[»]
    4FGKX-ray1.40A/B1-231[»]
    4FGLX-ray1.20A/B/C/D1-231[»]
    4GQIX-ray1.95A/B2-231[»]
    4GR9X-ray2.29A/B2-231[»]
    4QODX-ray1.35A/B1-231[»]
    4QOEX-ray1.45A/B1-231[»]
    4QOFX-ray1.55A/B1-231[»]
    4QOGX-ray1.40A/B1-231[»]
    4QOHX-ray1.60A/B1-231[»]
    4QOIX-ray1.55A/B1-231[»]
    4QOJX-ray1.85A/B1-231[»]
    4U7FX-ray1.80A/B2-231[»]
    4U7GX-ray1.96A/B2-231[»]
    4U7HX-ray1.48A/B2-231[»]
    4XDGX-ray1.50A/B1-231[»]
    4XDHX-ray1.90A/B1-231[»]
    4ZVKX-ray1.87A/B2-231[»]
    4ZVLX-ray1.90A/B2-231[»]
    4ZVMX-ray1.97A/B2-231[»]
    4ZVNX-ray1.87A/B2-231[»]
    5BUCX-ray1.87A/B2-231[»]
    5LBTX-ray1.75A/B1-231[»]
    5LBUX-ray1.65A/B1-231[»]
    DisProtiDP00727.
    ProteinModelPortaliP16083.
    SMRiP16083.
    ModBaseiSearch...
    MobiDBiSearch...

    Protein-protein interaction databases

    BioGridi110898. 12 interactors.
    IntActiP16083. 11 interactors.
    MINTiMINT-1133243.
    STRINGi9606.ENSP00000337773.

    Chemistry databases

    BindingDBiP16083.
    ChEMBLiCHEMBL3959.
    DrugBankiDB06695. Dabigatran etexilate.
    DB03147. Flavin adenine dinucleotide.
    DB01065. Melatonin.
    DB00170. Menadione.
    DB01087. Primaquine.

    PTM databases

    iPTMnetiP16083.
    PhosphoSitePlusiP16083.

    Polymorphism and mutation databases

    BioMutaiNQO2.
    DMDMi317373581.

    Proteomic databases

    EPDiP16083.
    MaxQBiP16083.
    PaxDbiP16083.
    PeptideAtlasiP16083.
    PRIDEiP16083.

    Protocols and materials databases

    Structural Biology KnowledgebaseSearch...

    Genome annotation databases

    EnsembliENST00000338130; ENSP00000337773; ENSG00000124588.
    ENST00000380430; ENSP00000369795; ENSG00000124588.
    ENST00000380455; ENSP00000369822; ENSG00000124588.
    GeneIDi4835.
    KEGGihsa:4835.
    UCSCiuc003mus.3. human.

    Organism-specific databases

    CTDi4835.
    DisGeNETi4835.
    GeneCardsiNQO2.
    H-InvDBHIX0018967.
    HGNCiHGNC:7856. NQO2.
    HPAiHPA021283.
    HPA021332.
    MalaCardsiNQO2.
    MIMi160998. gene.
    neXtProtiNX_P16083.
    OpenTargetsiENSG00000124588.
    PharmGKBiPA31745.
    GenAtlasiSearch...

    Phylogenomic databases

    eggNOGiENOG410IKWF. Eukaryota.
    COG2249. LUCA.
    GeneTreeiENSGT00440000033410.
    HOGENOMiHOG000149970.
    HOVERGENiHBG029104.
    InParanoidiP16083.
    KOiK08071.
    OMAiRLQTIWK.
    OrthoDBiEOG091G183R.
    PhylomeDBiP16083.
    TreeFamiTF300296.

    Enzyme and pathway databases

    BioCyciZFISH:HS04802-MONOMER.
    BRENDAi1.10.99.2. 2681.
    SABIO-RKP16083.

    Miscellaneous databases

    EvolutionaryTraceiP16083.
    GeneWikiiNAD(P)H_dehydrogenase,_quinone_2.
    GenomeRNAii4835.
    PROiP16083.
    SOURCEiSearch...

    Gene expression databases

    BgeeiENSG00000124588.
    CleanExiHS_NQO2.
    ExpressionAtlasiP16083. baseline and differential.
    GenevisibleiP16083. HS.

    Family and domain databases

    Gene3Di3.40.50.360. 1 hit.
    InterProiIPR003680. Flavodoxin_fold.
    IPR029039. Flavoprotein-like_dom.
    [Graphical view]
    PfamiPF02525. Flavodoxin_2. 1 hit.
    [Graphical view]
    SUPFAMiSSF52218. SSF52218. 1 hit.
    ProtoNetiSearch...

    Entry informationi

    Entry nameiNQO2_HUMAN
    AccessioniPrimary (citable) accession number: P16083
    Secondary accession number(s): B2R492, Q5TD04
    Entry historyi
    Integrated into UniProtKB/Swiss-Prot: April 1, 1990
    Last sequence update: January 11, 2011
    Last modified: November 30, 2016
    This is version 182 of the entry and version 5 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

    Uses dihydronicotinamide riboside (NRH) rather than NAD(P)H as an electron donor.

    Keywords - Technical termi

    3D-structure, Complete proteome, Reference proteome

    Documents

    1. Human chromosome 6
      Human chromosome 6: 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. 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.