Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Receptor-type tyrosine-protein phosphatase zeta

Gene

Ptprz1

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

Functioni

Protein tyrosine phosphatase that negatively regulates oligodendrocyte precursor proliferation in the embryonic spinal cord. Required for normal differentiation of the precursor cells into mature, fully myelinating oligodendrocytes. May play a role in protecting oligondendrocytes against apoptosis. May play a role in the establishment of contextual memory, probably via the dephosphorylation of proteins that are part of important signaling cascades (By similarity).By similarity
Isoform 3 (phosphacan), previously designated 3F8 chondroitin sulfate proteoglycan or 3H1 keratan sulfate proteoglycan depending on the glycosylation status, is a soluble nervous tissue-specific proteoglycan. It is synthesized by glia and binds to neurons and to the neural cell adhesion molecules tenascin, N-CAM or NG-CAM but not to laminin and fibronectin. Phosphacan acts as a potent inhibitor of cell adhesion and neurite outgrowth.

Catalytic activityi

Protein tyrosine phosphate + H2O = protein tyrosine + phosphate.PROSITE-ProRule annotation1 Publication

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei1902SubstrateBy similarity1
Active sitei1934Phosphocysteine intermediatePROSITE-ProRule annotation1
Binding sitei1978SubstrateBy similarity1
Sitei2224Ancestral active site1

GO - Molecular functioni

  • fibroblast growth factor binding Source: RGD
  • phosphatase activity Source: RGD
  • protein tyrosine phosphatase activity Source: UniProtKB

GO - Biological processi

  • axonal fasciculation Source: RGD
  • brain development Source: RGD
  • hippocampus development Source: RGD
  • learning or memory Source: UniProtKB
  • negative regulation of cell proliferation Source: RGD
  • negative regulation of cell-substrate adhesion Source: RGD
  • negative regulation of dendrite development Source: RGD
  • neuron development Source: RGD
  • oligodendrocyte differentiation Source: UniProtKB
  • peptidyl-tyrosine dephosphorylation Source: UniProtKB
  • positive regulation of cell migration Source: RGD
  • positive regulation of dendrite development Source: RGD
  • positive regulation of fibroblast proliferation Source: RGD
  • positive regulation of neuron death Source: RGD
  • positive regulation of neuron migration Source: RGD
  • positive regulation of neuron projection development Source: RGD
  • positive regulation of peptidyl-tyrosine phosphorylation Source: RGD
  • positive regulation of Schwann cell migration Source: RGD
  • protein dephosphorylation Source: RGD
  • regulation of dendrite morphogenesis Source: RGD
  • regulation of oligodendrocyte progenitor proliferation Source: UniProtKB
  • visual learning Source: RGD
Complete GO annotation...

Keywords - Molecular functioni

Hydrolase, Protein phosphatase

Names & Taxonomyi

Protein namesi
Recommended name:
Receptor-type tyrosine-protein phosphatase zeta (EC:3.1.3.481 Publication)
Short name:
R-PTP-zeta
Alternative name(s):
3F8 chondroitin sulfate proteoglycan
3H1 keratan sulfate proteoglycan
Phosphacan
Gene namesi
Name:Ptprz1
Synonyms:Ptprz, Ptpz
OrganismiRattus norvegicus (Rat)
Taxonomic identifieri10116 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeRattus
Proteomesi
  • UP000002494 Componenti: Unplaced

Organism-specific databases

RGDi3455. Ptprz1.

Subcellular locationi

Isoform 1 :

Topology

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Topological domaini25 – 1637ExtracellularSequence analysisAdd BLAST1613
Transmembranei1638 – 1663HelicalSequence analysisAdd BLAST26
Topological domaini1664 – 2316CytoplasmicSequence analysisAdd BLAST653

GO - Cellular componenti

  • axon Source: RGD
  • cytoplasm Source: RGD
  • dendrite Source: RGD
  • dendritic spine Source: RGD
  • extracellular space Source: RGD
  • filopodium Source: RGD
  • growth cone Source: RGD
  • integral component of membrane Source: UniProtKB-KW
  • intrinsic component of plasma membrane Source: UniProtKB
  • lamellipodium Source: RGD
  • membrane Source: RGD
  • neuronal cell body Source: RGD
  • perineuronal net Source: RGD
  • postsynaptic membrane Source: RGD
  • ruffle membrane Source: RGD
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Membrane, Secreted

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 24Add BLAST24
ChainiPRO_000002546925 – 2316Receptor-type tyrosine-protein phosphatase zetaAdd BLAST2292

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Disulfide bondi56 ↔ 240By similarity
Glycosylationi105N-linked (GlcNAc...)Sequence analysis1
Disulfide bondi133 ↔ 264By similarity
Glycosylationi134N-linked (GlcNAc...)Sequence analysis1
Glycosylationi223N-linked (GlcNAc...)Sequence analysis1
Glycosylationi232N-linked (GlcNAc...)Sequence analysis1
Glycosylationi324N-linked (GlcNAc...)Sequence analysis1
Glycosylationi381N-linked (GlcNAc...)Sequence analysis1
Glycosylationi497N-linked (GlcNAc...)Sequence analysis1
Glycosylationi552N-linked (GlcNAc...)Sequence analysis1
Modified residuei572PhosphoserineCombined sources1
Modified residuei576PhosphoserineCombined sources1
Glycosylationi595O-linked (Xyl...) (chondroitin sulfate)Sequence analysis1
Glycosylationi610N-linked (GlcNAc...)Sequence analysis1
Modified residuei645Phosphoserine; alternateCombined sources1
Glycosylationi645O-linked (Xyl...) (chondroitin sulfate); alternateSequence analysis1
Modified residuei647PhosphoserineCombined sources1
Glycosylationi685N-linked (GlcNAc...)Sequence analysis1
Glycosylationi786N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1005O-linked (Xyl...) (chondroitin sulfate)Sequence analysis1
Glycosylationi1025N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1058N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1463N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1550O-linked (Xyl...) (chondroitin sulfate)Sequence analysis1
Glycosylationi1552O-linked (Xyl...) (chondroitin sulfate)Sequence analysis1
Glycosylationi1563N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1611N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1619N-linked (GlcNAc...)Sequence analysis1
Modified residuei1685PhosphothreonineBy similarity1
Modified residuei1688PhosphothreonineCombined sources1
Modified residuei2056PhosphoserineBy similarity1

Keywords - PTMi

Disulfide bond, Glycoprotein, Phosphoprotein

Proteomic databases

PaxDbiQ62656.
PRIDEiQ62656.

PTM databases

iPTMnetiQ62656.
PhosphoSitePlusiQ62656.
SwissPalmiQ62656.

Expressioni

Tissue specificityi

Nervous tissue specific.

Interactioni

Subunit structurei

Interacts with tenascin (PubMed:7512960). Interacts with N-CAM and NG-CAM (PubMed:7528221). The carbonic-anhydrase like domain interacts with CNTN1 (contactin) (PubMed:7628014). Interacts with PTN (PubMed:16814777). Interaction with PTN promotes formation of homooligomers; oligomerization impairs phosphatase activity (PubMed:16814777).4 Publications

GO - Molecular functioni

  • fibroblast growth factor binding Source: RGD

Protein-protein interaction databases

DIPiDIP-59715N.
STRINGi10116.ENSRNOP00000008719.

Structurei

3D structure databases

ProteinModelPortaliQ62656.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini36 – 300Alpha-carbonic anhydrasePROSITE-ProRule annotationAdd BLAST265
Domaini314 – 413Fibronectin type-IIIPROSITE-ProRule annotationAdd BLAST100
Domaini1718 – 1993Tyrosine-protein phosphatase 1PROSITE-ProRule annotationAdd BLAST276
Domaini2024 – 2283Tyrosine-protein phosphatase 2PROSITE-ProRule annotationAdd BLAST260

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni1934 – 1940Substrate bindingBy similarity7

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi951 – 954Poly-Ser4
Compositional biasi1225 – 1230Poly-Ser6
Compositional biasi1426 – 1439Poly-AspAdd BLAST14

Sequence similaritiesi

Contains 1 alpha-carbonic anhydrase domain.PROSITE-ProRule annotation
Contains 1 fibronectin type-III domain.PROSITE-ProRule annotation
Contains 2 tyrosine-protein phosphatase domains.PROSITE-ProRule annotation

Keywords - Domaini

Repeat, Signal, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG4228. Eukaryota.
COG5599. LUCA.
HOGENOMiHOG000090262.
HOVERGENiHBG053760.
InParanoidiQ62656.
KOiK08114.
PhylomeDBiQ62656.

Family and domain databases

CDDicd00063. FN3. 1 hit.
Gene3Di2.60.40.10. 1 hit.
3.10.200.10. 1 hit.
3.90.190.10. 2 hits.
InterProiIPR001148. Carbonic_anhydrase_a.
IPR003961. FN3_dom.
IPR013783. Ig-like_fold.
IPR029021. Prot-tyrosine_phosphatase-like.
IPR000242. PTPase_domain.
IPR016130. Tyr_Pase_AS.
IPR003595. Tyr_Pase_cat.
IPR000387. TYR_PHOSPHATASE_dom.
[Graphical view]
PfamiPF00194. Carb_anhydrase. 1 hit.
PF00041. fn3. 1 hit.
PF00102. Y_phosphatase. 2 hits.
[Graphical view]
PRINTSiPR00700. PRTYPHPHTASE.
SMARTiSM01057. Carb_anhydrase. 1 hit.
SM00060. FN3. 1 hit.
SM00194. PTPc. 2 hits.
SM00404. PTPc_motif. 2 hits.
[Graphical view]
SUPFAMiSSF49265. SSF49265. 1 hit.
SSF51069. SSF51069. 1 hit.
SSF52799. SSF52799. 2 hits.
PROSITEiPS51144. ALPHA_CA_2. 1 hit.
PS50853. FN3. 1 hit.
PS00383. TYR_PHOSPHATASE_1. 1 hit.
PS50056. TYR_PHOSPHATASE_2. 2 hits.
PS50055. TYR_PHOSPHATASE_PTP. 2 hits.
[Graphical view]

Sequences (3)i

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

This entry describes 3 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q62656-1) [UniParc]FASTAAdd to basket
Also known as: Long

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
MRILQSFLAC VQLLCVCRLD WAYGYYRQQR KLVEEIGWSY TGALNQKNWG
60 70 80 90 100
KKYPICNSPK QSPINIDEDL TQVNVNLKKL KFQGWEKPSL ENTFIHNTGK
110 120 130 140 150
TVEINLTNDY YLSGGLSEKV FKASKMTFHW GKCNVSSEGS EHSLEGQKFP
160 170 180 190 200
LEMQIYCFDA DRFSSFEETV KGKGRLRALS ILFEIGVEEN LDYKAIIDGT
210 220 230 240 250
ESVSRFGKQA ALDPFILQNL LPNSTDKYYI YNGSLTSPPC TDTVEWIVFK
260 270 280 290 300
DTVSISESQL AVFCEVLTMQ QSGYVMLMDY LQNNFREQQY KFSRQVFSSY
310 320 330 340 350
TGKEEIHEAV CSSEPENVQA DPENYTSLLI TWERPRVVYD TMIEKFAVLY
360 370 380 390 400
QPLEGNDQTK HEFLTDGYQD LGAILNNLIP NMSYVLQIVA ICSNGLYGKY
410 420 430 440 450
SDQLIVDMPT EDAELDLFPE LIGTEEIIKE ENYGKGNEED TGLNPGRDSA
460 470 480 490 500
TNQIRKKEPQ VSTTTHYNHM GTKYNEAKTN RSPTRGSEFS GKSDVLNTSL
510 520 530 540 550
NPTSQQVAEF NPEREMSLPS QIGTNLPPHS VEGTSASLNS GSKTLLVFPQ
560 570 580 590 600
MNLSGTAESL NMVSITEYKE VSADLSEEEN LLTDFKLDSG ADDSSGSSPA
610 620 630 640 650
SSTVPFSTDN LSHGYTSSSD TPEAVTYDVL RPESTRNALE DSAPSGSEES
660 670 680 690 700
LKDPSLEGSV WFPGSTDLTT QSETGSGREG FLQVNSTDFQ VDESRETTET
710 720 730 740 750
FSPDATASRG PSVTDMEMPH YSTFAYPPTE VTSHAFTPSS RPLDLAPTSN
760 770 780 790 800
ILHSQTTQPV YNGETPLQPS YSSEVFPLVT PLLLDNQTLN TTPAASSSDS
810 820 830 840 850
ALHATPVFPS VGVSFDSILS SYDDAPLLPF SSASFSSDLF HHLHTVSQTL
860 870 880 890 900
PQVTSAAERD ELSLHASLLV AGGDLLLEPS LVQYSDVMSH QVTIHAASDT
910 920 930 940 950
LEFGSESAVL YKTSMVSQIE SPSSDVVMHA YSSGPETSYA IEGSHHVLTV
960 970 980 990 1000
SSSSAIPVHD SVGVADQGSL LINPSHISLP ESSFITPTAS LLQLPPALSG
1010 1020 1030 1040 1050
DGEWSGASSD SELLLPDTDG LRTLNMSSPV SVADFTYTTS VSGDDIKPLS
1060 1070 1080 1090 1100
KGEMMYGNET ELKMSSFSDM AYPSKSTVVP KMSDIVNKWS ESLKETSVSV
1110 1120 1130 1140 1150
SSINSVFTES LVYPITKVFD QEISRVPEII FPVKPTHTAS QASGDTWLKP
1160 1170 1180 1190 1200
GLSTNSEPAL SDTASSEVSH PSTQPLLYEA ASPFNTEALL QPSFPASDVD
1210 1220 1230 1240 1250
TLLKTALPSG PRDPVLTETP MVEQSSSSVS LPLASESASS KSTLHFTSVP
1260 1270 1280 1290 1300
VLNMSPSDVH PTSLQRLTVP HSREEYFEQG LLKSKSPQQV LPSLHSHDEF
1310 1320 1330 1340 1350
FQTAHLDISQ AYPPKGRHAF ATPILSINEP QNTLINRLVY SEDIFMHPEI
1360 1370 1380 1390 1400
SITDKALTGL PTTVSDVLIA TDHSVPLGSG PISMTTVSPN RDDSVTTTKL
1410 1420 1430 1440 1450
LLPSKATSKP THSARSDADL VGGGEDGDDY DDDDYDDIDS DRFPVNKCMS
1460 1470 1480 1490 1500
CSPYRESQEK VMNDSDTQES SLVDQSDPIS HLLSENTEEE NGGTGVTRVD
1510 1520 1530 1540 1550
KSPDKSPPPS MLPQKHNDGR EDRDIQMGSA VLPHTPGSKA WAVLTSDEES
1560 1570 1580 1590 1600
GSGQGTSDSL NDNETSTDFS FPDVNEKDAD GVLEADDTGI APGSPRSSTP
1610 1620 1630 1640 1650
SVTSGHSGVS NSSEAEASNS SHESRIGLAE GLESEKKAVI PLVIVSALTF
1660 1670 1680 1690 1700
ICLVVLVGIL IYWRKCFQTA HFYLEDNTSP RVISTPPTPI FPISDDIGAI
1710 1720 1730 1740 1750
PIKHFPKHVA DLHASNGFTE EFETLKEFYQ EVQSCTVDLG ITADSSNHPD
1760 1770 1780 1790 1800
NKHKNRYVNI VAYDHSRVKL TQLAEKDGKL TDYINANYVD GYNRPKAYIA
1810 1820 1830 1840 1850
AQGPLKSTAE DFWRMIWEHN VEVIVMITNL VEKGRRKCDQ YWPTDGSEEY
1860 1870 1880 1890 1900
GSFLVNQKNV QVLAYYTVRN FTLRNTKIKK GSQKGRSSGR LVTQYHYTQW
1910 1920 1930 1940 1950
PDMGVPEYSL PVLAFVRKTA QAKRHAVGPV VVHCSAGVGR TGTYIVLDSM
1960 1970 1980 1990 2000
LQQIQHEGTV NIFGFLKHIR SQRNYLVQTE EQYVFIHDTL VEAILSKETE
2010 2020 2030 2040 2050
VPDSHIHSYV NTLLIPGPSG KTKLEKQFQL LSQSNILQSD YSTALKQCNR
2060 2070 2080 2090 2100
EKNRTSSIIP VERSRVGISS LSGEGTDYIN ASYIMGYYQS NEFIITQHPL
2110 2120 2130 2140 2150
LHTIKDFWRM IWDHNAQLVV MIPDGQNMAE DEFVYWPNKD EPINCESFKV
2160 2170 2180 2190 2200
TLMSEEHKCL SNEEKLIVQD FILEATQDDY VLEVRHFQCP KWPNPDSPIS
2210 2220 2230 2240 2250
KTFELISIIK EEAANRDGPM IVHDEHGGVT AGTFCALTTL MHQLEKENSM
2260 2270 2280 2290 2300
DVYQVAKMIN LMRPGVFTDI EQYQFLYKVV LSLVSTRQEE NPSTSLDSNG
2310
AALPDGNIAE SLESLV
Length:2,316
Mass (Da):255,342
Last modified:November 1, 1996 - v1
Checksum:i419EA9B89BDD165F
GO
Isoform 2 (identifier: Q62656-2) [UniParc]FASTAAdd to basket
Also known as: Short

The sequence of this isoform differs from the canonical sequence as follows:
     763-1615: Missing.

Show »
Length:1,463
Mass (Da):164,596
Checksum:iFF524D7DA90C4BE0
GO
Isoform 3 (identifier: Q62656-3) [UniParc]FASTAAdd to basket
Also known as: Phosphacan

The sequence of this isoform differs from the canonical sequence as follows:
     1616-1616: E → G
     1617-2316: Missing.

Show »
Length:1,616
Mass (Da):175,839
Checksum:i6F02DDE391A41117
GO

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_005152763 – 1615Missing in isoform 2. 1 PublicationAdd BLAST853
Alternative sequenceiVSP_0051531616E → G in isoform 3. 1 Publication1
Alternative sequenceiVSP_0051541617 – 2316Missing in isoform 3. 1 PublicationAdd BLAST700

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U09357 mRNA. Translation: AAC52207.1.
U04998 mRNA. Translation: AAC52383.1.
PIRiA40169.
RefSeqiNP_001164156.1. NM_001170685.1.
NP_037212.2. NM_013080.2.
UniGeneiRn.10088.

Genome annotation databases

GeneIDi25613.
KEGGirno:25613.
UCSCiRGD:3455. rat. [Q62656-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U09357 mRNA. Translation: AAC52207.1.
U04998 mRNA. Translation: AAC52383.1.
PIRiA40169.
RefSeqiNP_001164156.1. NM_001170685.1.
NP_037212.2. NM_013080.2.
UniGeneiRn.10088.

3D structure databases

ProteinModelPortaliQ62656.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

DIPiDIP-59715N.
STRINGi10116.ENSRNOP00000008719.

PTM databases

iPTMnetiQ62656.
PhosphoSitePlusiQ62656.
SwissPalmiQ62656.

Proteomic databases

PaxDbiQ62656.
PRIDEiQ62656.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

GeneIDi25613.
KEGGirno:25613.
UCSCiRGD:3455. rat. [Q62656-1]

Organism-specific databases

CTDi5803.
RGDi3455. Ptprz1.

Phylogenomic databases

eggNOGiKOG4228. Eukaryota.
COG5599. LUCA.
HOGENOMiHOG000090262.
HOVERGENiHBG053760.
InParanoidiQ62656.
KOiK08114.
PhylomeDBiQ62656.

Miscellaneous databases

PROiQ62656.

Family and domain databases

CDDicd00063. FN3. 1 hit.
Gene3Di2.60.40.10. 1 hit.
3.10.200.10. 1 hit.
3.90.190.10. 2 hits.
InterProiIPR001148. Carbonic_anhydrase_a.
IPR003961. FN3_dom.
IPR013783. Ig-like_fold.
IPR029021. Prot-tyrosine_phosphatase-like.
IPR000242. PTPase_domain.
IPR016130. Tyr_Pase_AS.
IPR003595. Tyr_Pase_cat.
IPR000387. TYR_PHOSPHATASE_dom.
[Graphical view]
PfamiPF00194. Carb_anhydrase. 1 hit.
PF00041. fn3. 1 hit.
PF00102. Y_phosphatase. 2 hits.
[Graphical view]
PRINTSiPR00700. PRTYPHPHTASE.
SMARTiSM01057. Carb_anhydrase. 1 hit.
SM00060. FN3. 1 hit.
SM00194. PTPc. 2 hits.
SM00404. PTPc_motif. 2 hits.
[Graphical view]
SUPFAMiSSF49265. SSF49265. 1 hit.
SSF51069. SSF51069. 1 hit.
SSF52799. SSF52799. 2 hits.
PROSITEiPS51144. ALPHA_CA_2. 1 hit.
PS50853. FN3. 1 hit.
PS00383. TYR_PHOSPHATASE_1. 1 hit.
PS50056. TYR_PHOSPHATASE_2. 2 hits.
PS50055. TYR_PHOSPHATASE_PTP. 2 hits.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPTPRZ_RAT
AccessioniPrimary (citable) accession number: Q62656
Secondary accession number(s): Q62621
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 15, 1998
Last sequence update: November 1, 1996
Last modified: November 30, 2016
This is version 151 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Direct protein sequencing, 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.