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Protein

Potassium channel subfamily K member 2

Gene

Kcnk2

Organism
Rattus norvegicus (Rat)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Ion channel that contributes to passive transmembrane potassium transport. Reversibly converts between a voltage-insensitive potassium leak channel and a voltage-dependent outward rectifying potassium channel in a phosphorylation-dependent manner (PubMed:11319556). In astrocytes, forms mostly heterodimeric potassium channels with KCNK1, with only a minor proportion of functional channels containing homodimeric KCNK2. In astrocytes, the heterodimer formed by KCNK1 and KCNK2 is required for rapid glutamate release in response to activation of G-protein coupled receptors, such as F2R and CNR1 (By similarity).By similarity1 Publication
Isoform 5: Does not display channel activity but reduces the channel activity of isoform 1, isoform 2 and isoform 4 and reduces cell surface expression of isoform 2.1 Publication

GO - Molecular functioni

  • outward rectifier potassium channel activity Source: UniProtKB
  • potassium channel inhibitor activity Source: UniProtKB
  • potassium ion leak channel activity Source: UniProtKB

GO - Biological processi

  • cardiac ventricle development Source: RGD
  • cellular response to hypoxia Source: RGD
  • cochlea development Source: RGD
  • G-protein coupled receptor signaling pathway Source: Ensembl
  • memory Source: RGD
  • negative regulation of cardiac muscle cell proliferation Source: RGD
  • negative regulation of DNA biosynthetic process Source: RGD
  • positive regulation of cell death Source: RGD
  • positive regulation of cellular response to hypoxia Source: RGD
  • potassium ion transmembrane transport Source: GOC
  • regulation of membrane potential Source: Ensembl
  • response to axon injury Source: RGD
  • response to mechanical stimulus Source: RGD
Complete GO annotation...

Keywords - Molecular functioni

Ion channel

Keywords - Biological processi

Ion transport, Transport

Enzyme and pathway databases

ReactomeiR-RNO-1299503. TWIK related potassium channel (TREK).

Names & Taxonomyi

Protein namesi
Recommended name:
Potassium channel subfamily K member 2By similarity
Alternative name(s):
Outward rectifying potassium channel protein TREK-1By similarity
Stretch-activated potassium channel TREK-11 Publication
TREK-1 K(+) channel subunitBy similarity
Two pore domain potassium channel TREK-11 Publication
Two pore potassium channel TPKC1By similarity
Gene namesi
Name:Kcnk2Imported
Synonyms:TrekImported
OrganismiRattus norvegicus (Rat)
Taxonomic identifieri10116 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeRattus
Proteomesi
  • UP000002494 Componenti: Chromosome 13

Organism-specific databases

RGDi621448. Kcnk2.

Subcellular locationi

Isoform 1 :
Isoform 2 :
Isoform 5 :

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 6161CytoplasmicSequence analysisAdd
BLAST
Transmembranei62 – 8221HelicalSequence analysisAdd
BLAST
Intramembranei144 – 17027Pore-forming; Name=Pore-forming 1Sequence analysisAdd
BLAST
Transmembranei172 – 19221HelicalSequence analysisAdd
BLAST
Topological domaini193 – 22230CytoplasmicSequence analysisAdd
BLAST
Transmembranei223 – 24321HelicalSequence analysisAdd
BLAST
Intramembranei253 – 28331Pore-forming; Name=Pore-forming 2Sequence analysisAdd
BLAST
Transmembranei288 – 30821HelicalSequence analysisAdd
BLAST
Topological domaini309 – 426118CytoplasmicSequence analysisAdd
BLAST

GO - Cellular componenti

  • apical plasma membrane Source: RGD
  • astrocyte projection Source: RGD
  • axon Source: RGD
  • axon terminus Source: RGD
  • calyx of Held Source: RGD
  • cell surface Source: RGD
  • endoplasmic reticulum Source: UniProtKB
  • endoplasmic reticulum membrane Source: UniProtKB-SubCell
  • integral component of plasma membrane Source: UniProtKB
  • neuronal cell body Source: RGD
  • neuron projection Source: RGD
  • nucleus Source: RGD
  • plasma membrane Source: UniProtKB
  • voltage-gated potassium channel complex Source: Ensembl
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Endoplasmic reticulum, Membrane

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 426426Potassium channel subfamily K member 2PRO_0000426718Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi108 – 108InterchainBy similarity
Glycosylationi110 – 1101N-linked (GlcNAc...)Sequence analysis
Glycosylationi134 – 1341N-linked (GlcNAc...)Sequence analysis
Modified residuei348 – 3481Phosphoserine; by PKABy similarity

Post-translational modificationi

Phosphorylation at Ser-348 controls the reversible conversion from a leak channel to a voltage-dependent channel.By similarity

Keywords - PTMi

Disulfide bond, Glycoprotein, Phosphoprotein

Proteomic databases

PaxDbiQ920B6.

Expressioni

Tissue specificityi

Expressed in cardiomyocytes (at protein level). Expressed in various brain regions including the lateral olfactory tract, piriform cortex of the forebrain, paraventricular and anteromedial thalamic nuclei, brainstem, caudate putamen, nucleus accumbens, neocortex and interpeduncular nucleus. Isoform 5 is expressed in brain and kidney.3 Publications

Gene expression databases

GenevisibleiQ920B6. RN.

Interactioni

Subunit structurei

Homodimer; disulfide-linked (By similarity). Heterodimer with KCNK1; disulfide-linked (By similarity). Interacts with KCNK2; the interaction enhances KCNK2 surface expression (By similarity).By similarity

Binary interactionsi

WithEntry#Exp.IntActNotes
GNG4P501503EBI-6530063,EBI-6395970From a different organism.

Protein-protein interaction databases

IntActiQ920B6. 9 interactions.
STRINGi10116.ENSRNOP00000003684.

Structurei

3D structure databases

ProteinModelPortaliQ920B6.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni354 – 42673Required for basal channel activityBy similarityAdd
BLAST
Regioni378 – 42649Essential for chloroform and halothane sensitivityBy similarityAdd
BLAST

Domaini

The C-terminal region of isoform 5 mediates its intracellular retention.1 Publication

Sequence similaritiesi

Keywords - Domaini

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG1418. Eukaryota.
COG1226. LUCA.
GeneTreeiENSGT00760000118858.
HOGENOMiHOG000013106.
HOVERGENiHBG052234.
InParanoidiQ920B6.
KOiK04913.
OMAiAINVMKW.
OrthoDBiEOG77M8NK.
PhylomeDBiQ920B6.
TreeFamiTF313947.

Family and domain databases

InterProiIPR003280. 2pore_dom_K_chnl.
IPR003976. 2pore_dom_K_chnl_TREK.
IPR013099. K_chnl_dom.
[Graphical view]
PfamiPF07885. Ion_trans_2. 2 hits.
[Graphical view]
PRINTSiPR01333. 2POREKCHANEL.
PR01499. TREKCHANNEL.

Sequences (5)i

Sequence statusi: Complete.

This entry describes 5 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 12 Publications (identifier: Q920B6-1) [UniParc]FASTAAdd to basket

Also known as: TREK-1b1 Publication

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
MLASASRERP GYTAGVAAPD LLDPKSAAQN SKPRLSFSAK PTVLASRVES
60 70 80 90 100
DSAINVMKWK TVSTIFLVVV LYLIIGATVF KALEQPQEIS QRTTIVIQKQ
110 120 130 140 150
NFIAQHACVN STELDELIQQ IVTAINAGII PLGNNSNQVS HWDLGSSFFF
160 170 180 190 200
AGTVITTIGF GNISPRTEGG KIFCIIYALL GIPLFGFLLA GVGDQLGTIF
210 220 230 240 250
GKGIAKVEDT FIKWNVSQTK IRIISTIIFI LFGCVLFVAL PAVIFKHIEG
260 270 280 290 300
WSALDAIYFV VITLTTIGFG DYVAGGSDIE YLDFYKPVVW FWILVGLAYF
310 320 330 340 350
AAVLSMIGDW LRVISKKTKE EVGEFRAHAA EWTANVTAEF KETRRRLSVE
360 370 380 390 400
IYDKFQRATS VKRKLSAELA GNHNQELTPC RRTLSVNHLT SEREVLPPLL
410 420
KAESIYLNGL TPHCAAEDIA VIENMK
Length:426
Mass (Da):46,912
Last modified:December 1, 2001 - v1
Checksum:iCACDA05BBE95FDBC
GO
Isoform 21 Publication (identifier: Q920B6-2) [UniParc]FASTAAdd to basket

Also known as: TREK-1a1 Publication

The sequence of this isoform differs from the canonical sequence as follows:
     2-16: Missing.

Show »
Length:411
Mass (Da):45,396
Checksum:iAEA49DEB352F1F93
GO
Isoform 31 Publication (identifier: Q920B6-3) [UniParc]FASTAAdd to basket

Also known as: TREK-1c1 Publication

The sequence of this isoform differs from the canonical sequence as follows:
     1-16: MLASASRERPGYTAGV → MMNPRAKRSVYL

Show »
Length:422
Mass (Da):46,712
Checksum:iF93C93197D1D5EA2
GO
Isoform 41 Publication (identifier: Q920B6-4) [UniParc]FASTAAdd to basket

Also known as: TREK-1d1 Publication

The sequence of this isoform differs from the canonical sequence as follows:
     1-15: MLASASRERPGYTAG → MGA

Show »
Length:414
Mass (Da):45,623
Checksum:i6111010B94D42D5E
GO
Isoform 51 Publication (identifier: Q920B6-5) [UniParc]FASTAAdd to basket

Also known as: TREK-1e1 Publication

The sequence of this isoform differs from the canonical sequence as follows:
     2-16: Missing.
     213-241: KWNVSQTKIRIISTIIFILFGCVLFVALP → VGRTLNIWTSTSSSCGSGSSLGWPTLRLF
     242-426: Missing.

Show »
Length:226
Mass (Da):24,225
Checksum:iA78944060F5D788E
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti416 – 4161A → R in ABD64605 (PubMed:24196565).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 1616MLASA…YTAGV → MMNPRAKRSVYL in isoform 3. 1 PublicationVSP_053952Add
BLAST
Alternative sequencei1 – 1515MLASA…GYTAG → MGA in isoform 4. 1 PublicationVSP_053953Add
BLAST
Alternative sequencei2 – 1615Missing in isoform 2 and isoform 5. 2 PublicationsVSP_053954Add
BLAST
Alternative sequencei213 – 24129KWNVS…FVALP → VGRTLNIWTSTSSSCGSGSS LGWPTLRLF in isoform 5. 1 PublicationVSP_053955Add
BLAST
Alternative sequencei242 – 426185Missing in isoform 5. 1 PublicationVSP_053956Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF325671 mRNA. Translation: AAL01159.1.
AF385402 mRNA. Translation: AAL95708.1.
AY727922 mRNA. Translation: AAU25945.1.
AY555072 mRNA. Translation: AAT64134.1.
AY555073 mRNA. Translation: AAT64135.1.
DQ403851 mRNA. Translation: ABD64605.1.
AY695826 mRNA. Translation: AAU06141.1.
AABR06076806 Genomic DNA. No translation available.
AABR06076807 Genomic DNA. No translation available.
AABR06076808 Genomic DNA. No translation available.
AABR06076809 Genomic DNA. No translation available.
CH473985 Genomic DNA. Translation: EDL94961.1.
CH473985 Genomic DNA. Translation: EDL94962.1.
RefSeqiNP_742038.2. NM_172041.2.
NP_742039.1. NM_172042.1. [Q920B6-1]
XP_006250495.1. XM_006250433.2. [Q920B6-4]
XP_006250496.1. XM_006250434.2. [Q920B6-2]
UniGeneiRn.21984.

Genome annotation databases

EnsembliENSRNOT00000003684; ENSRNOP00000003684; ENSRNOG00000002653. [Q920B6-1]
ENSRNOT00000077282; ENSRNOP00000068842; ENSRNOG00000002653. [Q920B6-3]
GeneIDi170899.
KEGGirno:170899.
UCSCiRGD:621448. rat. [Q920B6-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF325671 mRNA. Translation: AAL01159.1.
AF385402 mRNA. Translation: AAL95708.1.
AY727922 mRNA. Translation: AAU25945.1.
AY555072 mRNA. Translation: AAT64134.1.
AY555073 mRNA. Translation: AAT64135.1.
DQ403851 mRNA. Translation: ABD64605.1.
AY695826 mRNA. Translation: AAU06141.1.
AABR06076806 Genomic DNA. No translation available.
AABR06076807 Genomic DNA. No translation available.
AABR06076808 Genomic DNA. No translation available.
AABR06076809 Genomic DNA. No translation available.
CH473985 Genomic DNA. Translation: EDL94961.1.
CH473985 Genomic DNA. Translation: EDL94962.1.
RefSeqiNP_742038.2. NM_172041.2.
NP_742039.1. NM_172042.1. [Q920B6-1]
XP_006250495.1. XM_006250433.2. [Q920B6-4]
XP_006250496.1. XM_006250434.2. [Q920B6-2]
UniGeneiRn.21984.

3D structure databases

ProteinModelPortaliQ920B6.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

IntActiQ920B6. 9 interactions.
STRINGi10116.ENSRNOP00000003684.

Proteomic databases

PaxDbiQ920B6.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSRNOT00000003684; ENSRNOP00000003684; ENSRNOG00000002653. [Q920B6-1]
ENSRNOT00000077282; ENSRNOP00000068842; ENSRNOG00000002653. [Q920B6-3]
GeneIDi170899.
KEGGirno:170899.
UCSCiRGD:621448. rat. [Q920B6-1]

Organism-specific databases

CTDi3776.
RGDi621448. Kcnk2.

Phylogenomic databases

eggNOGiKOG1418. Eukaryota.
COG1226. LUCA.
GeneTreeiENSGT00760000118858.
HOGENOMiHOG000013106.
HOVERGENiHBG052234.
InParanoidiQ920B6.
KOiK04913.
OMAiAINVMKW.
OrthoDBiEOG77M8NK.
PhylomeDBiQ920B6.
TreeFamiTF313947.

Enzyme and pathway databases

ReactomeiR-RNO-1299503. TWIK related potassium channel (TREK).

Miscellaneous databases

NextBioi621313.
PROiQ920B6.

Gene expression databases

GenevisibleiQ920B6. RN.

Family and domain databases

InterProiIPR003280. 2pore_dom_K_chnl.
IPR003976. 2pore_dom_K_chnl_TREK.
IPR013099. K_chnl_dom.
[Graphical view]
PfamiPF07885. Ion_trans_2. 2 hits.
[Graphical view]
PRINTSiPR01333. 2POREKCHANEL.
PR01499. TREKCHANNEL.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "KCNK2: reversible conversion of a hippocampal potassium leak into a voltage-dependent channel."
    Bockenhauer D., Zilberberg N., Goldstein S.A.
    Nat. Neurosci. 4:486-491(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), FUNCTION.
    Tissue: BrainImported.
  2. "Expression pattern and functional characteristics of two novel splice variants of the two-pore-domain potassium channel TREK-2."
    Gu W., Schlichthorl G., Hirsch J.R., Engels H., Karschin C., Karschin A., Derst C., Steinlein O.K., Daut J.
    J. Physiol. (Lond.) 539:657-668(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), TISSUE SPECIFICITY.
    Strain: WistarImported.
  3. "The stretch-activated potassium channel TREK-1 in rat cardiac ventricular muscle."
    Tao Li X., Dyachenko V., Zuzarte M., Putzke C., Preisig-Muller R., Isenberg G., Daut J.
    Cardiovasc. Res. 69:86-97(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2), TISSUE SPECIFICITY, ACTIVATION.
  4. "A splice variant of the two-pore domain potassium channel TREK-1 with only one pore domain reduces the surface expression of full-length TREK-1 channels."
    Rinne S., Renigunta V., Schlichthorl G., Zuzarte M., Bittner S., Meuth S.G., Decher N., Daut J., Preisig-Muller R.
    Pflugers Arch. 466:1559-1570(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 3; 4 AND 5), FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, DOMAIN.
  5. "Possible role of TREK-1 in temperature regulation."
    Li Z.B., Wang X.L.
    Submitted (JUL-2004) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Strain: WistarImported.
  6. "Genome sequence of the Brown Norway rat yields insights into mammalian evolution."
    Gibbs R.A., Weinstock G.M., Metzker M.L., Muzny D.M., Sodergren E.J., Scherer S., Scott G., Steffen D., Worley K.C., Burch P.E., Okwuonu G., Hines S., Lewis L., Deramo C., Delgado O., Dugan-Rocha S., Miner G., Morgan M.
    , Hawes A., Gill R., Holt R.A., Adams M.D., Amanatides P.G., Baden-Tillson H., Barnstead M., Chin S., Evans C.A., Ferriera S., Fosler C., Glodek A., Gu Z., Jennings D., Kraft C.L., Nguyen T., Pfannkoch C.M., Sitter C., Sutton G.G., Venter J.C., Woodage T., Smith D., Lee H.-M., Gustafson E., Cahill P., Kana A., Doucette-Stamm L., Weinstock K., Fechtel K., Weiss R.B., Dunn D.M., Green E.D., Blakesley R.W., Bouffard G.G., De Jong P.J., Osoegawa K., Zhu B., Marra M., Schein J., Bosdet I., Fjell C., Jones S., Krzywinski M., Mathewson C., Siddiqui A., Wye N., McPherson J., Zhao S., Fraser C.M., Shetty J., Shatsman S., Geer K., Chen Y., Abramzon S., Nierman W.C., Havlak P.H., Chen R., Durbin K.J., Egan A., Ren Y., Song X.-Z., Li B., Liu Y., Qin X., Cawley S., Cooney A.J., D'Souza L.M., Martin K., Wu J.Q., Gonzalez-Garay M.L., Jackson A.R., Kalafus K.J., McLeod M.P., Milosavljevic A., Virk D., Volkov A., Wheeler D.A., Zhang Z., Bailey J.A., Eichler E.E., Tuzun E., Birney E., Mongin E., Ureta-Vidal A., Woodwark C., Zdobnov E., Bork P., Suyama M., Torrents D., Alexandersson M., Trask B.J., Young J.M., Huang H., Wang H., Xing H., Daniels S., Gietzen D., Schmidt J., Stevens K., Vitt U., Wingrove J., Camara F., Mar Alba M., Abril J.F., Guigo R., Smit A., Dubchak I., Rubin E.M., Couronne O., Poliakov A., Huebner N., Ganten D., Goesele C., Hummel O., Kreitler T., Lee Y.-A., Monti J., Schulz H., Zimdahl H., Himmelbauer H., Lehrach H., Jacob H.J., Bromberg S., Gullings-Handley J., Jensen-Seaman M.I., Kwitek A.E., Lazar J., Pasko D., Tonellato P.J., Twigger S., Ponting C.P., Duarte J.M., Rice S., Goodstadt L., Beatson S.A., Emes R.D., Winter E.E., Webber C., Brandt P., Nyakatura G., Adetobi M., Chiaromonte F., Elnitski L., Eswara P., Hardison R.C., Hou M., Kolbe D., Makova K., Miller W., Nekrutenko A., Riemer C., Schwartz S., Taylor J., Yang S., Zhang Y., Lindpaintner K., Andrews T.D., Caccamo M., Clamp M., Clarke L., Curwen V., Durbin R.M., Eyras E., Searle S.M., Cooper G.M., Batzoglou S., Brudno M., Sidow A., Stone E.A., Payseur B.A., Bourque G., Lopez-Otin C., Puente X.S., Chakrabarti K., Chatterji S., Dewey C., Pachter L., Bray N., Yap V.B., Caspi A., Tesler G., Pevzner P.A., Haussler D., Roskin K.M., Baertsch R., Clawson H., Furey T.S., Hinrichs A.S., Karolchik D., Kent W.J., Rosenbloom K.R., Trumbower H., Weirauch M., Cooper D.N., Stenson P.D., Ma B., Brent M., Arumugam M., Shteynberg D., Copley R.R., Taylor M.S., Riethman H., Mudunuri U., Peterson J., Guyer M., Felsenfeld A., Old S., Mockrin S., Collins F.S.
    Nature 428:493-521(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: Brown NorwayImported.
  7. Mural R.J., Adams M.D., Myers E.W., Smith H.O., Venter J.C.
    Submitted (JUL-2005) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].

Entry informationi

Entry nameiKCNK2_RAT
AccessioniPrimary (citable) accession number: Q920B6
Secondary accession number(s): A3QR52
, Q3MMY3, Q5DNW4, Q5DNW5
Entry historyi
Integrated into UniProtKB/Swiss-Prot: April 16, 2014
Last sequence update: December 1, 2001
Last modified: May 11, 2016
This is version 99 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Miscellaneous

Activated by arachadonic acid, mechanical stretching and intracellular acidification.1 Publication

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. 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.