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Protein

Tropomyosin alpha-1 chain

Gene

Tpm1

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

Functioni

Binds to actin filaments in muscle and non-muscle cells. Plays a central role, in association with the troponin complex, in the calcium dependent regulation of vertebrate striated muscle contraction. Smooth muscle contraction is regulated by interaction with caldesmon. In non-muscle cells is implicated in stabilizing cytoskeleton actin filaments.

GO - Molecular functioni

  • actin binding Source: RGD
  • actin filament binding Source: RGD
  • protein homodimerization activity Source: RGD
  • protein N-terminus binding Source: RGD

GO - Biological processi

  • actin filament capping Source: RGD
  • cardiac muscle contraction Source: RGD
  • muscle contraction Source: RGD
  • muscle filament sliding Source: BHF-UCL
  • negative regulation of cell migration Source: BHF-UCL
  • positive regulation of ATPase activity Source: BHF-UCL
  • positive regulation of cell adhesion Source: BHF-UCL
  • positive regulation of stress fiber assembly Source: BHF-UCL
  • regulation of ATPase activity Source: RGD
  • ruffle organization Source: BHF-UCL
  • wound healing Source: BHF-UCL
Complete GO annotation...

Keywords - Molecular functioni

Muscle protein

Keywords - Ligandi

Actin-binding

Enzyme and pathway databases

ReactomeiREACT_281385. Smooth Muscle Contraction.
REACT_283017. Striated Muscle Contraction.

Names & Taxonomyi

Protein namesi
Recommended name:
Tropomyosin alpha-1 chain
Alternative name(s):
Alpha-tropomyosin
Tropomyosin-1
Gene namesi
Name:Tpm1
Synonyms:Alpha-tm, Tpma
OrganismiRattus norvegicus (Rat)
Taxonomic identifieri10116 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeRattus
ProteomesiUP000002494 Componenti: Chromosome 8

Organism-specific databases

RGDi3898. Tpm1.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: UniProtKB-KW
  • cytoskeleton Source: UniProtKB-SubCell
  • protein complex Source: RGD
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Cytoskeleton

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 284284Tropomyosin alpha-1 chainPRO_0000205624Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei1 – 11N-acetylmethionineBy similarity
Modified residuei53 – 531PhosphothreonineBy similarity
Modified residuei61 – 611PhosphoserineBy similarity
Cross-linki77 – 77Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)By similarity
Modified residuei79 – 791PhosphothreonineBy similarity
Modified residuei108 – 1081PhosphothreonineBy similarity
Modified residuei174 – 1741PhosphoserineBy similarity
Modified residuei206 – 2061PhosphoserineBy similarity
Modified residuei282 – 2821PhosphothreonineBy similarity
Modified residuei283 – 2831Phosphoserine; by DAPK1By similarity

Post-translational modificationi

Phosphorylated at Ser-283 by DAPK1 in response to oxidative stress and this phosphorylation enhances stress fiber formation in endothelial cells.By similarity

Keywords - PTMi

Acetylation, Isopeptide bond, Phosphoprotein, Ubl conjugation

Proteomic databases

PaxDbiP04692.
PRIDEiP04692.

PTM databases

PhosphoSiteiP04692.

Expressioni

Gene expression databases

ExpressionAtlasiP04692. baseline and differential.
GenevisibleiP04692. RN.

Interactioni

Subunit structurei

Heterodimer of an alpha and a beta chain. Interacts with HRG (via the HRR domain); the interaction contributes to the antiangiogenic properties of the histidine/proline-rich region (HRR) of HRG (By similarity).By similarity

Protein-protein interaction databases

BioGridi246968. 5 interactions.
DIPiDIP-29020N.
IntActiP04692. 2 interactions.

Structurei

Secondary structure

1
284
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi2 – 1413Combined sources
Turni95 – 973Combined sources
Helixi100 – 1034Combined sources
Turni104 – 1074Combined sources
Helixi108 – 12316Combined sources
Helixi125 – 20884Combined sources
Helixi254 – 28128Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1IHQNMR-A/B206-209[»]
1MV4NMR-A/B251-284[»]
1TMZNMR-A/B1-14[»]
2B9CX-ray2.30A/B89-208[»]
2G9JNMR-A/B1-14[»]
C/D251-284[»]
3AZDX-ray0.98A/B206-209[»]
ProteinModelPortaliP04692.
SMRiP04692. Positions 8-284.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP04692.

Family & Domainsi

Coiled coil

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Coiled coili1 – 284284Add
BLAST

Domaini

The molecule is in a coiled coil structure that is formed by 2 polypeptide chains. The sequence exhibits a prominent seven-residues periodicity.

Sequence similaritiesi

Belongs to the tropomyosin family.Curated

Keywords - Domaini

Coiled coil

Phylogenomic databases

eggNOGiNOG304012.
GeneTreeiENSGT00550000074494.
HOVERGENiHBG107404.
InParanoidiP04692.
KOiK10373.
PhylomeDBiP04692.
TreeFamiTF351519.

Family and domain databases

InterProiIPR000533. Tropomyosin.
[Graphical view]
PfamiPF00261. Tropomyosin. 1 hit.
[Graphical view]
PRINTSiPR00194. TROPOMYOSIN.
PROSITEiPS00326. TROPOMYOSIN. 1 hit.
[Graphical view]

Sequences (8)i

Sequence statusi: Complete.

This entry describes 8 isoformsi produced by alternative splicing. AlignAdd to basket

Note: Additional isoforms seem to exist.

Isoform 1 (identifier: P04692-1) [UniParc]FASTAAdd to basket

Also known as: Skeletal muscle

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
MDAIKKKMQM LKLDKENALD RAEQAEADKK AAEDRSKQLE DELVSLQKKL
60 70 80 90 100
KGTEDELDKY SEALKDAQEK LELAEKKATD AEADVASLNR RIQLVEEELD
110 120 130 140 150
RAQERLATAL QKLEEAEKAA DESERGMKVI ESRAQKDEEK MEIQEIQLKE
160 170 180 190 200
AKHIAEDADR KYEEVARKLV IIESDLERAE ERAELSEGKC AELEEELKTV
210 220 230 240 250
TNNLKSLEAQ AEKYSQKEDK YEEEIKVLSD KLKEAETRAE FAERSVTKLE
260 270 280
KSIDDLEDEL YAQKLKYKAI SEELDHALND MTSI
Length:284
Mass (Da):32,681
Last modified:April 4, 2006 - v3
Checksum:iE25609F597A72F4D
GO
Isoform 2 (identifier: P04692-2) [UniParc]FASTAAdd to basket

Also known as: Smooth muscle

The sequence of this isoform differs from the canonical sequence as follows:
     41-80: DELVSLQKKL...LELAEKKATD → EDISAKEKLL...LLAADETAAK
     258-284: DELYAQKLKYKAISEELDHALNDMTSI → EKVAHAKEENLSMHQMLHQTLLELNNM

Show »
Length:284
Mass (Da):32,676
Checksum:i35056246C3FFA678
GO
Isoform 3 (identifier: P04692-3) [UniParc]FASTAAdd to basket

Also known as: Brain TMBr-1

The sequence of this isoform differs from the canonical sequence as follows:
     259-284: ELYAQKLKYKAISEELDHALNDMTSI → QLYHQLEQNRRLTNELKLALNED

Show »
Length:281
Mass (Da):32,495
Checksum:iE8CA06AF0B96E230
GO
Isoform 4 (identifier: P04692-4) [UniParc]FASTAAdd to basket

Also known as: Brain TMBr-2

The sequence of this isoform differs from the canonical sequence as follows:
     1-80: MDAIKKKMQM...LELAEKKATD → MAGSSSLEAV...LDQERKLRET
     259-284: ELYAQKLKYKAISEELDHALNDMTSI → KFLCFSPPKTPSSSRMSHLSELCICLLSS

Show »
Length:251
Mass (Da):28,704
Checksum:iC361AFDF972CC474
GO
Isoform 5 (identifier: P04692-5) [UniParc]FASTAAdd to basket

Also known as: Brain TMBr-3

The sequence of this isoform differs from the canonical sequence as follows:
     1-80: MDAIKKKMQM...LELAEKKATD → MAGSSSLEAV...LDQERKLRET
     259-284: ELYAQKLKYKAISEELDHALNDMTSI → QLYHQLEQNRRLTNELKLALNED

Show »
Length:245
Mass (Da):28,343
Checksum:iFD9E17F1B920550F
GO
Isoform 6 (identifier: P04692-6) [UniParc]FASTAAdd to basket

Also known as: Fibroblast TM-2

The sequence of this isoform differs from the canonical sequence as follows:
     258-284: DELYAQKLKYKAISEELDHALNDMTSI → EKVAHAKEENLSMHQMLHQTLLELNNM

Show »
Length:284
Mass (Da):32,731
Checksum:iCD7A66BFAEA04540
GO
Isoform 7 (identifier: P04692-7) [UniParc]FASTAAdd to basket

Also known as: Fibroblast 5a

The sequence of this isoform differs from the canonical sequence as follows:
     1-80: MDAIKKKMQM...LELAEKKATD → MAGSSSLEAV...LDQERKLRET
     258-284: DELYAQKLKYKAISEELDHALNDMTSI → EKVAHAKEENLSMHQMLHQTLLELNNM

Show »
Length:248
Mass (Da):28,579
Checksum:i3D2B523AFAB11BF2
GO
Isoform 8 (identifier: P04692-8) [UniParc]FASTAAdd to basket

Also known as: Fibroblast 5b

The sequence of this isoform differs from the canonical sequence as follows:
     1-80: MDAIKKKMQM...LELAEKKATD → MAGSSSLEAV...LDQERKLRET
     189-212: KCAELEEELKTVTNNLKSLEAQAE → QVRQLEEQLRIMDQTLKALMAAED
     258-284: DELYAQKLKYKAISEELDHALNDMTSI → EKVAHAKEENLSMHQMLHQTLLELNNM

Show »
Length:248
Mass (Da):28,718
Checksum:i1AC7D77131E5F251
GO

Sequence cautioni

Isoform 2 : The sequence CAA26258.1 differs from that shown.miscellaneous discrepancyCurated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti52 – 521G → A in AAA42252 (PubMed:2320008).Curated
Sequence conflicti279 – 2791N → K in AAA21801 (PubMed:3558368).Curated
Sequence conflicti279 – 2791N → K in AAA21805 (PubMed:3352602).Curated
Isoform 7 (identifier: P04692-7)
Sequence conflicti239 – 2391H → D in AAA18098 (PubMed:2022655).Curated
Isoform 8 (identifier: P04692-8)
Sequence conflicti239 – 2391H → D in AAA18099 (PubMed:2022655).Curated
Isoform 2 (identifier: P04692-2)
Sequence conflicti260 – 2601V → G in CAA26258 (PubMed:3838802).Curated
Sequence conflicti275 – 2751H → D in CAA26258 (PubMed:3838802).Curated
Isoform 6 (identifier: P04692-6)
Sequence conflicti275 – 2751H → D in AAA42290 (PubMed:2022655).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 8080MDAIK…KKATD → MAGSSSLEAVRRKIRSLQEQ ADAAEERAGSLQRELDQERK LRET in isoform 4, isoform 5, isoform 7 and isoform 8. 2 PublicationsVSP_006581Add
BLAST
Alternative sequencei41 – 8040DELVS…KKATD → EDISAKEKLLRASEDERDRV LEELHKAEDSLLAADETAAK in isoform 2. 1 PublicationVSP_006582Add
BLAST
Alternative sequencei189 – 21224KCAEL…EAQAE → QVRQLEEQLRIMDQTLKALM AAED in isoform 8. 1 PublicationVSP_006583Add
BLAST
Alternative sequencei258 – 28427DELYA…DMTSI → EKVAHAKEENLSMHQMLHQT LLELNNM in isoform 2, isoform 6, isoform 7 and isoform 8. 2 PublicationsVSP_006584Add
BLAST
Alternative sequencei259 – 28426ELYAQ…DMTSI → QLYHQLEQNRRLTNELKLAL NED in isoform 3 and isoform 5. 1 PublicationVSP_006585Add
BLAST
Alternative sequencei259 – 28426ELYAQ…DMTSI → KFLCFSPPKTPSSSRMSHLS ELCICLLSS in isoform 4. 1 PublicationVSP_006586Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M15474
, M15472, M15473, M16432, M16433 Genomic DNA. Translation: AAA21801.1.
M18135
, M16432, M15472, M16433, M15473 Genomic DNA. Translation: AAA21803.1. Different termination.
M18135, M16432, M16433 Genomic DNA. Translation: AAA21804.1.
M18135
, M16432, M15472, M16433 Genomic DNA. Translation: AAA21805.1.
X02411 mRNA. Translation: CAA26258.1. Sequence problems.
M34135 mRNA. Translation: AAA42252.1.
M34134 mRNA. Translation: AAA42253.1.
M34136 mRNA. Translation: AAA42254.1.
M34137 Genomic DNA. Translation: AAA40773.1.
M34138 Genomic DNA. Translation: AAA40774.1.
M60666 mRNA. Translation: AAA42290.1.
M60668 mRNA. Translation: AAA18098.1.
M60669 mRNA. Translation: AAA18099.1.
X02412 mRNA. Translation: CAA26259.1.
PIRiA34787.
A39816.
B27407.
B34787.
C34787.
C39816.
D39816.
RefSeqiNP_001029241.1. NM_001034069.1.
NP_001029244.1. NM_001034072.1. [P04692-3]
NP_001029245.1. NM_001034073.1.
NP_001029246.1. NM_001034074.1.
NP_001029247.1. NM_001034075.1.
NP_001288265.1. NM_001301336.1. [P04692-1]
NP_001288665.1. NM_001301736.1. [P04692-5]
NP_062004.1. NM_019131.2. [P04692-4]
UniGeneiRn.87540.

Genome annotation databases

EnsembliENSRNOT00000024575; ENSRNOP00000024575; ENSRNOG00000018184. [P04692-3]
ENSRNOT00000048044; ENSRNOP00000048499; ENSRNOG00000018184. [P04692-1]
GeneIDi24851.
KEGGirno:24851.

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M15474
, M15472, M15473, M16432, M16433 Genomic DNA. Translation: AAA21801.1.
M18135
, M16432, M15472, M16433, M15473 Genomic DNA. Translation: AAA21803.1. Different termination.
M18135, M16432, M16433 Genomic DNA. Translation: AAA21804.1.
M18135
, M16432, M15472, M16433 Genomic DNA. Translation: AAA21805.1.
X02411 mRNA. Translation: CAA26258.1. Sequence problems.
M34135 mRNA. Translation: AAA42252.1.
M34134 mRNA. Translation: AAA42253.1.
M34136 mRNA. Translation: AAA42254.1.
M34137 Genomic DNA. Translation: AAA40773.1.
M34138 Genomic DNA. Translation: AAA40774.1.
M60666 mRNA. Translation: AAA42290.1.
M60668 mRNA. Translation: AAA18098.1.
M60669 mRNA. Translation: AAA18099.1.
X02412 mRNA. Translation: CAA26259.1.
PIRiA34787.
A39816.
B27407.
B34787.
C34787.
C39816.
D39816.
RefSeqiNP_001029241.1. NM_001034069.1.
NP_001029244.1. NM_001034072.1. [P04692-3]
NP_001029245.1. NM_001034073.1.
NP_001029246.1. NM_001034074.1.
NP_001029247.1. NM_001034075.1.
NP_001288265.1. NM_001301336.1. [P04692-1]
NP_001288665.1. NM_001301736.1. [P04692-5]
NP_062004.1. NM_019131.2. [P04692-4]
UniGeneiRn.87540.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1IHQNMR-A/B206-209[»]
1MV4NMR-A/B251-284[»]
1TMZNMR-A/B1-14[»]
2B9CX-ray2.30A/B89-208[»]
2G9JNMR-A/B1-14[»]
C/D251-284[»]
3AZDX-ray0.98A/B206-209[»]
ProteinModelPortaliP04692.
SMRiP04692. Positions 8-284.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi246968. 5 interactions.
DIPiDIP-29020N.
IntActiP04692. 2 interactions.

PTM databases

PhosphoSiteiP04692.

Proteomic databases

PaxDbiP04692.
PRIDEiP04692.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSRNOT00000024575; ENSRNOP00000024575; ENSRNOG00000018184. [P04692-3]
ENSRNOT00000048044; ENSRNOP00000048499; ENSRNOG00000018184. [P04692-1]
GeneIDi24851.
KEGGirno:24851.

Organism-specific databases

CTDi7168.
RGDi3898. Tpm1.

Phylogenomic databases

eggNOGiNOG304012.
GeneTreeiENSGT00550000074494.
HOVERGENiHBG107404.
InParanoidiP04692.
KOiK10373.
PhylomeDBiP04692.
TreeFamiTF351519.

Enzyme and pathway databases

ReactomeiREACT_281385. Smooth Muscle Contraction.
REACT_283017. Striated Muscle Contraction.

Miscellaneous databases

EvolutionaryTraceiP04692.
NextBioi301732.
PROiP04692.

Gene expression databases

ExpressionAtlasiP04692. baseline and differential.
GenevisibleiP04692. RN.

Family and domain databases

InterProiIPR000533. Tropomyosin.
[Graphical view]
PfamiPF00261. Tropomyosin. 1 hit.
[Graphical view]
PRINTSiPR00194. TROPOMYOSIN.
PROSITEiPS00326. TROPOMYOSIN. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

  1. "Comparison of alpha-tropomyosin sequences from smooth and striated muscle."
    Ruiz-Opazo N., Weinberger J., Nadal-Ginard B.
    Nature 315:67-70(1985) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2).
  2. "Alpha-tropomyosin gene organization. Alternative splicing of duplicated isotype-specific exons accounts for the production of smooth and striated muscle isoforms."
    Ruiz-Opazo N., Nadal-Ginard B.
    J. Biol. Chem. 262:4755-4765(1987) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], ALTERNATIVE SPLICING.
  3. "The rat alpha-tropomyosin gene generates a minimum of six different mRNAs coding for striated, smooth, and nonmuscle isoforms by alternative splicing."
    Wieczorek D.F., Smith C.W., Nadal-Ginard B.
    Mol. Cell. Biol. 8:679-694(1988) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], ALTERNATIVE SPLICING.
  4. "Three novel brain tropomyosin isoforms are expressed from the rat alpha-tropomyosin gene through the use of alternative promoters and alternative RNA processing."
    Lees-Miller J.P., Goodwin L.O., Helfman D.M.
    Mol. Cell. Biol. 10:1729-1742(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORMS 3; 4 AND 5).
    Tissue: Brain.
  5. "Four fibroblast tropomyosin isoforms are expressed from the rat alpha-tropomyosin gene via alternative RNA splicing and the use of two promoters."
    Goodwin L.O., Lees-Miller J.P., Leonard M.A., Cheley S.B., Helfman D.M.
    J. Biol. Chem. 266:8408-8415(1991) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 6; 7 AND 8).
  6. "Cloning and characterization of cDNA sequences corresponding to myosin light chains 1, 2, and 3, troponin-C, troponin-T, alpha-tropomyosin, and alpha-actin."
    Garfinkel L.I., Periasamy M., Nadal-Ginard B.
    J. Biol. Chem. 257:11078-11086(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: PARTIAL NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
  7. Lubec G., Afjehi-Sadat L., Diao W., Kang S.U., Lubec S.
    Submitted (SEP-2007) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 92-101; 141-149; 218-226 AND 251-270, PARTIAL PROTEIN SEQUENCE (ISOFORMS 4/5/7/8), IDENTIFICATION BY MASS SPECTROMETRY.
    Strain: Sprague-Dawley.
    Tissue: Brain, Hippocampus and Spinal cord.
  8. "Specificity of dimer formation in tropomyosins: influence of alternatively spliced exons on homodimer and heterodimer assembly."
    Gimona M., Watakabe A., Helfman D.M.
    Proc. Natl. Acad. Sci. U.S.A. 92:9776-9780(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: SUBUNIT.

Entry informationi

Entry nameiTPM1_RAT
AccessioniPrimary (citable) accession number: P04692
Secondary accession number(s): P06469
, P18342, P18343, P18344, P19354, Q53X09, Q63582, Q63608, Q63609
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 13, 1987
Last sequence update: April 4, 2006
Last modified: June 24, 2015
This is version 136 of the entry and version 3 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

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

External Data

Dasty 3

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 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.