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Q9UL51

- HCN2_HUMAN

UniProt

Q9UL51 - HCN2_HUMAN

Protein

Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2

Gene

HCN2

Organism
Homo sapiens (Human)
Status
Reviewed - Annotation score: 5 out of 5- Experimental evidence at protein leveli
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    • History
      Entry version 123 (01 Oct 2014)
      Sequence version 3 (13 Jun 2006)
      Previous versions | rss
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    Functioni

    Hyperpolarization-activated ion channel exhibiting weak selectivity for potassium over sodium ions. Contributes to the native pacemaker currents in heart (If) and in neurons (Ih). Can also transport ammonium in the distal nephron. Produces a large instantaneous current. Modulated by intracellular chloride ions and pH; acidic pH shifts the activation to more negative voltages By similarity.By similarity

    Enzyme regulationi

    Activated by cAMP, and at 10-100 times higher concentrations, also by cGMP. cAMP binding causes a conformation change that leads to the assembly of an active tetramer and channel opening. Channel activity is modulated by intracellular chloride ions and pH; acidic pH shifts the activation to more negative voltages.2 Publications

    Regions

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Nucleotide bindingi608 – 6114cAMP1 Publication
    Nucleotide bindingi618 – 6192cAMP1 Publication
    Nucleotide bindingi659 – 6624cAMP1 Publication

    GO - Molecular functioni

    1. cAMP binding Source: UniProtKB-KW
    2. identical protein binding Source: IntAct
    3. intracellular cAMP activated cation channel activity Source: UniProtKB
    4. voltage-gated potassium channel activity Source: UniProtKB
    5. voltage-gated sodium channel activity Source: UniProt

    GO - Biological processi

    1. cell-cell signaling Source: ProtInc
    2. cellular response to cAMP Source: UniProtKB
    3. cellular response to cGMP Source: UniProt
    4. potassium ion transmembrane transport Source: UniProtKB
    5. regulation of membrane potential Source: UniProt
    6. sodium ion transmembrane transport Source: UniProt
    7. synaptic transmission Source: Reactome

    Keywords - Molecular functioni

    Ion channel, Ligand-gated ion channel, Potassium channel, Sodium channel, Voltage-gated channel

    Keywords - Biological processi

    Ion transport, Potassium transport, Sodium transport, Transport

    Keywords - Ligandi

    cAMP, cAMP-binding, Nucleotide-binding, Potassium, Sodium

    Enzyme and pathway databases

    ReactomeiREACT_75862. HCN channels.

    Protein family/group databases

    TCDBi1.A.1.5.11. the voltage-gated ion channel (vic) superfamily.

    Names & Taxonomyi

    Protein namesi
    Recommended name:
    Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2
    Alternative name(s):
    Brain cyclic nucleotide-gated channel 2
    Short name:
    BCNG-2
    Gene namesi
    Name:HCN2
    Synonyms:BCNG2
    OrganismiHomo sapiens (Human)
    Taxonomic identifieri9606 [NCBI]
    Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
    ProteomesiUP000005640: Chromosome 19

    Organism-specific databases

    HGNCiHGNC:4846. HCN2.

    Subcellular locationi

    Cell membrane 2 Publications; Multi-pass membrane protein 2 Publications

    GO - Cellular componenti

    1. integral component of plasma membrane Source: UniProtKB
    2. plasma membrane Source: UniProt
    3. voltage-gated potassium channel complex Source: ProtInc

    Keywords - Cellular componenti

    Cell membrane, Membrane

    Pathology & Biotechi

    Organism-specific databases

    PharmGKBiPA78.

    PTM / Processingi

    Molecule processing

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Chaini1 – 889889Potassium/sodium hyperpolarization-activated cyclic nucleotide-gated channel 2PRO_0000054111Add
    BLAST

    Amino acid modifications

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Glycosylationi407 – 4071N-linked (GlcNAc...)Sequence Analysis
    Modified residuei668 – 6681Phosphoserine; by PKG/PRKG2By similarity

    Post-translational modificationi

    Phosphorylation at Ser-668 by PRKG2 shifts the voltage-dependence to more negative voltages, hence counteracting the stimulatory effect of cGMP on gating.By similarity

    Keywords - PTMi

    Glycoprotein, Phosphoprotein

    Proteomic databases

    PaxDbiQ9UL51.
    PRIDEiQ9UL51.

    PTM databases

    PhosphoSiteiQ9UL51.

    Expressioni

    Tissue specificityi

    Highly expressed throughout the brain. Detected at low levels in heart.2 Publications

    Gene expression databases

    ArrayExpressiQ9UL51.
    BgeeiQ9UL51.
    CleanExiHS_HCN2.
    GenevestigatoriQ9UL51.

    Interactioni

    Subunit structurei

    The potassium channel is composed of a homo- or heterotetrameric complex of pore-forming subunits. Heterotetramer with HCN1. Forms an obligate 4:4 complex with accessory subunit PEX5L. Interacts with KCNE2 By similarity. Homotetramer.By similarity1 Publication

    Binary interactionsi

    WithEntry#Exp.IntActNotes
    itself2EBI-1751885,EBI-1751885

    Protein-protein interaction databases

    BioGridi107081. 4 interactions.
    IntActiQ9UL51. 4 interactions.
    STRINGi9606.ENSP00000251287.

    Structurei

    Secondary structure

    1
    889
    Legend: HelixTurnBeta strand
    Show more details
    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Helixi471 – 48919
    Helixi494 – 50815
    Helixi515 – 5206
    Helixi524 – 53411
    Helixi536 – 5405
    Turni543 – 5475
    Helixi550 – 5578
    Beta strandi561 – 5655
    Beta strandi570 – 5723
    Beta strandi580 – 5867
    Beta strandi589 – 5924
    Beta strandi598 – 6014
    Beta strandi606 – 6083
    Helixi610 – 6145
    Beta strandi619 – 6268
    Beta strandi628 – 6347
    Helixi635 – 64410
    Helixi646 – 66116
    Turni662 – 6643
    Helixi668 – 6703

    3D structure databases

    Select the link destinations:
    PDBe
    RCSB PDB
    PDBj
    Links Updated
    EntryMethodResolution (Å)ChainPositionsPDBsum
    3U10X-ray2.30A470-672[»]
    ProteinModelPortaliQ9UL51.
    SMRiQ9UL51. Positions 412-662.
    ModBaseiSearch...
    MobiDBiSearch...

    Topological domain

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Topological domaini1 – 215215CytoplasmicSequence AnalysisAdd
    BLAST
    Topological domaini237 – 2404ExtracellularSequence Analysis
    Topological domaini262 – 28827CytoplasmicSequence AnalysisAdd
    BLAST
    Topological domaini310 – 3178ExtracellularSequence Analysis
    Topological domaini339 – 36931CytoplasmicSequence AnalysisAdd
    BLAST
    Topological domaini391 – 41323ExtracellularSequence AnalysisAdd
    BLAST
    Topological domaini436 – 4405ExtracellularSequence Analysis
    Topological domaini462 – 889428CytoplasmicSequence AnalysisAdd
    BLAST

    Intramembrane

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Intramembranei414 – 43522Pore-forming; Name=Segment H5Sequence AnalysisAdd
    BLAST

    Transmembrane

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Transmembranei216 – 23621Helical; Name=Segment S1Sequence AnalysisAdd
    BLAST
    Transmembranei241 – 26121Helical; Name=Segment S2Sequence AnalysisAdd
    BLAST
    Transmembranei289 – 30921Helical; Name=Segment S3Sequence AnalysisAdd
    BLAST
    Transmembranei318 – 33821Helical; Voltage-sensor; Name=Segment S4Sequence AnalysisAdd
    BLAST
    Transmembranei370 – 39021Helical; Name=Segment S5Sequence AnalysisAdd
    BLAST
    Transmembranei441 – 46121Helical; Name=Segment S6Sequence AnalysisAdd
    BLAST

    Family & Domainsi

    Region

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Regioni158 – 20952Involved in subunit assemblyBy similarityAdd
    BLAST

    Compositional bias

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Compositional biasi10 – 140131Pro-richAdd
    BLAST
    Compositional biasi715 – 861147Pro-richAdd
    BLAST

    Domaini

    The segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position.

    Sequence similaritiesi

    Belongs to the potassium channel HCN family.Curated
    Contains 1 cyclic nucleotide-binding domain.PROSITE-ProRule annotation

    Keywords - Domaini

    Transmembrane, Transmembrane helix

    Phylogenomic databases

    eggNOGiCOG0664.
    HOGENOMiHOG000230717.
    HOVERGENiHBG039489.
    InParanoidiQ9UL51.
    KOiK04955.
    OMAiMRICNIS.
    OrthoDBiEOG7VMP6X.
    PhylomeDBiQ9UL51.
    TreeFamiTF318250.

    Family and domain databases

    Gene3Di2.60.120.10. 1 hit.
    InterProiIPR018490. cNMP-bd-like.
    IPR018488. cNMP-bd_CS.
    IPR000595. cNMP-bd_dom.
    IPR005821. Ion_trans_dom.
    IPR013621. Ion_trans_N.
    IPR003938. K_chnl_volt-dep_EAG/ELK/ERG.
    IPR014710. RmlC-like_jellyroll.
    [Graphical view]
    PfamiPF00027. cNMP_binding. 1 hit.
    PF00520. Ion_trans. 1 hit.
    PF08412. Ion_trans_N. 1 hit.
    [Graphical view]
    PRINTSiPR01463. EAGCHANLFMLY.
    SMARTiSM00100. cNMP. 1 hit.
    [Graphical view]
    SUPFAMiSSF51206. SSF51206. 1 hit.
    PROSITEiPS00888. CNMP_BINDING_1. 1 hit.
    PS50042. CNMP_BINDING_3. 1 hit.
    [Graphical view]

    Sequencei

    Sequence statusi: Complete.

    Q9UL51-1 [UniParc]FASTAAdd to Basket

    « Hide

    MDARGGGGRP GESPGATPAP GPPPPPPPAP PQQQPPPPPP PAPPPGPGPA    50
    PPQHPPRAEA LPPEAADEGG PRGRLRSRDS SCGRPGTPGA ASTAKGSPNG 100
    ECGRGEPQCS PAGPEGPARG PKVSFSCRGA ASGPAPGPGP AEEAGSEEAG 150
    PAGEPRGSQA SFMQRQFGAL LQPGVNKFSL RMFGSQKAVE REQERVKSAG 200
    AWIIHPYSDF RFYWDFTMLL FMVGNLIIIP VGITFFKDET TAPWIVFNVV 250
    SDTFFLMDLV LNFRTGIVIE DNTEIILDPE KIKKKYLRTW FVVDFVSSIP 300
    VDYIFLIVEK GIDSEVYKTA RALRIVRFTK ILSLLRLLRL SRLIRYIHQW 350
    EEIFHMTYDL ASAVMRICNL ISMMLLLCHW DGCLQFLVPM LQDFPRNCWV 400
    SINGMVNHSW SELYSFALFK AMSHMLCIGY GRQAPESMTD IWLTMLSMIV 450
    GATCYAMFIG HATALIQSLD SSRRQYQEKY KQVEQYMSFH KLPADFRQKI 500
    HDYYEHRYQG KMFDEDSILG ELNGPLREEI VNFNCRKLVA SMPLFANADP 550
    NFVTAMLTKL KFEVFQPGDY IIREGTIGKK MYFIQHGVVS VLTKGNKEMK 600
    LSDGSYFGEI CLLTRGRRTA SVRADTYCRL YSLSVDNFNE VLEEYPMMRR 650
    AFETVAIDRL DRIGKKNSIL LHKVQHDLNS GVFNNQENAI IQEIVKYDRE 700
    MVQQAELGQR VGLFPPPPPP PQVTSAIATL QQAAAMSFCP QVARPLVGPL 750
    ALGSPRLVRR PPPGPAPAAA SPGPPPPASP PGAPASPRAP RTSPYGGLPA 800
    APLAGPALPA RRLSRASRPL SASQPSLPHG APGPAASTRP ASSSTPRLGP 850
    TPAARAAAPS PDRRDSASPG AAGGLDPQDS ARSRLSSNL 889
    Length:889
    Mass (Da):96,950
    Last modified:June 13, 2006 - v3
    Checksum:i4B263E0C06C2A47D
    GO

    Experimental Info

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Sequence conflicti17 – 204TPAP → SPTT in AAC28444. (PubMed:10524219)Curated
    Sequence conflicti29 – 291A → R in AAC28444. (PubMed:10524219)Curated
    Sequence conflicti32 – 321Q → K in AAC28444. (PubMed:10524219)Curated
    Sequence conflicti294 – 2941D → V in AAC39760. (PubMed:9630217)Curated
    Sequence conflicti713 – 7131L → F in AAC39760. (PubMed:9630217)Curated
    Sequence conflicti849 – 8491G → R in CAB42602. (PubMed:10228147)Curated
    Sequence conflicti849 – 8491G → R in CAB42630. (PubMed:10228147)Curated

    Natural variant

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Natural varianti527 – 5271R → Q.
    Corresponds to variant rs55687900 [ dbSNP | Ensembl ].
    VAR_061106

    Sequence databases

    Select the link destinations:
    EMBL
    GenBank
    DDBJ
    Links Updated
    AF065164 mRNA. Translation: AAC28444.2.
    AJ012582 mRNA. Translation: CAB42602.1.
    AJ133727
    , AJ133728, AJ133729, AJ133730, AJ133731, AJ133732, AJ133733, AJ133734 Genomic DNA. Translation: CAB42630.1.
    AC004449 Genomic DNA. No translation available.
    AC005559 Genomic DNA. Translation: AAC33280.2.
    AF064877 mRNA. Translation: AAC39760.1.
    CCDSiCCDS12035.1.
    RefSeqiNP_001185.3. NM_001194.3.
    UniGeneiHs.124161.

    Genome annotation databases

    GeneIDi610.
    KEGGihsa:610.
    UCSCiuc002lpe.3. human.

    Polymorphism databases

    DMDMi108935843.

    Keywords - Coding sequence diversityi

    Polymorphism

    Cross-referencesi

    Sequence databases

    Select the link destinations:
    EMBL
    GenBank
    DDBJ
    Links Updated
    AF065164 mRNA. Translation: AAC28444.2 .
    AJ012582 mRNA. Translation: CAB42602.1 .
    AJ133727
    , AJ133728 , AJ133729 , AJ133730 , AJ133731 , AJ133732 , AJ133733 , AJ133734 Genomic DNA. Translation: CAB42630.1 .
    AC004449 Genomic DNA. No translation available.
    AC005559 Genomic DNA. Translation: AAC33280.2 .
    AF064877 mRNA. Translation: AAC39760.1 .
    CCDSi CCDS12035.1.
    RefSeqi NP_001185.3. NM_001194.3.
    UniGenei Hs.124161.

    3D structure databases

    Select the link destinations:
    PDBe
    RCSB PDB
    PDBj
    Links Updated
    Entry Method Resolution (Å) Chain Positions PDBsum
    3U10 X-ray 2.30 A 470-672 [» ]
    ProteinModelPortali Q9UL51.
    SMRi Q9UL51. Positions 412-662.
    ModBasei Search...
    MobiDBi Search...

    Protein-protein interaction databases

    BioGridi 107081. 4 interactions.
    IntActi Q9UL51. 4 interactions.
    STRINGi 9606.ENSP00000251287.

    Chemistry

    ChEMBLi CHEMBL1795172.
    GuidetoPHARMACOLOGYi 401.

    Protein family/group databases

    TCDBi 1.A.1.5.11. the voltage-gated ion channel (vic) superfamily.

    PTM databases

    PhosphoSitei Q9UL51.

    Polymorphism databases

    DMDMi 108935843.

    Proteomic databases

    PaxDbi Q9UL51.
    PRIDEi Q9UL51.

    Protocols and materials databases

    DNASUi 610.
    Structural Biology Knowledgebase Search...

    Genome annotation databases

    GeneIDi 610.
    KEGGi hsa:610.
    UCSCi uc002lpe.3. human.

    Organism-specific databases

    CTDi 610.
    GeneCardsi GC19P000589.
    HGNCi HGNC:4846. HCN2.
    MIMi 602781. gene.
    neXtProti NX_Q9UL51.
    PharmGKBi PA78.
    GenAtlasi Search...

    Phylogenomic databases

    eggNOGi COG0664.
    HOGENOMi HOG000230717.
    HOVERGENi HBG039489.
    InParanoidi Q9UL51.
    KOi K04955.
    OMAi MRICNIS.
    OrthoDBi EOG7VMP6X.
    PhylomeDBi Q9UL51.
    TreeFami TF318250.

    Enzyme and pathway databases

    Reactomei REACT_75862. HCN channels.

    Miscellaneous databases

    GeneWikii HCN2.
    GenomeRNAii 610.
    NextBioi 2477.
    PROi Q9UL51.
    SOURCEi Search...

    Gene expression databases

    ArrayExpressi Q9UL51.
    Bgeei Q9UL51.
    CleanExi HS_HCN2.
    Genevestigatori Q9UL51.

    Family and domain databases

    Gene3Di 2.60.120.10. 1 hit.
    InterProi IPR018490. cNMP-bd-like.
    IPR018488. cNMP-bd_CS.
    IPR000595. cNMP-bd_dom.
    IPR005821. Ion_trans_dom.
    IPR013621. Ion_trans_N.
    IPR003938. K_chnl_volt-dep_EAG/ELK/ERG.
    IPR014710. RmlC-like_jellyroll.
    [Graphical view ]
    Pfami PF00027. cNMP_binding. 1 hit.
    PF00520. Ion_trans. 1 hit.
    PF08412. Ion_trans_N. 1 hit.
    [Graphical view ]
    PRINTSi PR01463. EAGCHANLFMLY.
    SMARTi SM00100. cNMP. 1 hit.
    [Graphical view ]
    SUPFAMi SSF51206. SSF51206. 1 hit.
    PROSITEi PS00888. CNMP_BINDING_1. 1 hit.
    PS50042. CNMP_BINDING_3. 1 hit.
    [Graphical view ]
    ProtoNeti Search...

    Publicationsi

    1. Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, SUBCELLULAR LOCATION.
    2. "Two pacemaker channels from human heart with profoundly different activation kinetics."
      Ludwig A., Zong X., Stieber J., Hullin R., Hofmann F., Biel M.
      EMBO J. 18:2323-2329(1999) [PubMed] [Europe PMC] [Abstract]
      Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], FUNCTION, ENZYME REGULATION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
      Tissue: Heart.
    3. "The DNA sequence and biology of human chromosome 19."
      Grimwood J., Gordon L.A., Olsen A.S., Terry A., Schmutz J., Lamerdin J.E., Hellsten U., Goodstein D., Couronne O., Tran-Gyamfi M., Aerts A., Altherr M., Ashworth L., Bajorek E., Black S., Branscomb E., Caenepeel S., Carrano A.V.
      , Caoile C., Chan Y.M., Christensen M., Cleland C.A., Copeland A., Dalin E., Dehal P., Denys M., Detter J.C., Escobar J., Flowers D., Fotopulos D., Garcia C., Georgescu A.M., Glavina T., Gomez M., Gonzales E., Groza M., Hammon N., Hawkins T., Haydu L., Ho I., Huang W., Israni S., Jett J., Kadner K., Kimball H., Kobayashi A., Larionov V., Leem S.-H., Lopez F., Lou Y., Lowry S., Malfatti S., Martinez D., McCready P.M., Medina C., Morgan J., Nelson K., Nolan M., Ovcharenko I., Pitluck S., Pollard M., Popkie A.P., Predki P., Quan G., Ramirez L., Rash S., Retterer J., Rodriguez A., Rogers S., Salamov A., Salazar A., She X., Smith D., Slezak T., Solovyev V., Thayer N., Tice H., Tsai M., Ustaszewska A., Vo N., Wagner M., Wheeler J., Wu K., Xie G., Yang J., Dubchak I., Furey T.S., DeJong P., Dickson M., Gordon D., Eichler E.E., Pennacchio L.A., Richardson P., Stubbs L., Rokhsar D.S., Myers R.M., Rubin E.M., Lucas S.M.
      Nature 428:529-535(2004) [PubMed] [Europe PMC] [Abstract]
      Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    4. "Identification of a gene encoding a hyperpolarization-activated 'pacemaker' channel of brain."
      Santoro B., Liu D.T., Yao H., Bartsch D., Kandel E.R., Siegelbaum S.A., Tibbs G.R.
      Cell 93:717-729(1998) [PubMed] [Europe PMC] [Abstract]
      Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 147-743, TISSUE SPECIFICITY.
      Tissue: Brain.
    5. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
      Tissue: Cervix carcinoma.
    6. "Tetramerization dynamics of C-terminal domain underlies isoform-specific cAMP gating in hyperpolarization-activated cyclic nucleotide-gated channels."
      Lolicato M., Nardini M., Gazzarrini S., Moller S., Bertinetti D., Herberg F.W., Bolognesi M., Martin H., Fasolini M., Bertrand J.A., Arrigoni C., Thiel G., Moroni A.
      J. Biol. Chem. 286:44811-44820(2011) [PubMed] [Europe PMC] [Abstract]
      Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS) OF 470-672 IN COMPLEX WITH CAMP, NUCLEOTIDE-BINDING, ENZYME REGULATION, SUBUNIT.

    Entry informationi

    Entry nameiHCN2_HUMAN
    AccessioniPrimary (citable) accession number: Q9UL51
    Secondary accession number(s): O60742
    , O60743, O75267, Q9UBS2
    Entry historyi
    Integrated into UniProtKB/Swiss-Prot: February 28, 2003
    Last sequence update: June 13, 2006
    Last modified: October 1, 2014
    This is version 123 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

    Inhibited by extracellular cesium ions.

    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. PDB cross-references
      Index of Protein Data Bank (PDB) cross-references
    6. SIMILARITY comments
      Index of protein domains and families

    External Data

    Dasty 3