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Protein

Cyclin-dependent kinase 1

Gene

cdc2

Organism
Drosophila melanogaster (Fruit fly)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Plays a key role in the control of the eukaryotic cell cycle. It is required in higher cells for entry into S-phase and mitosis. p34 is a component of the kinase complex that phosphorylates the repetitive C-terminus of RNA polymerase II.1 Publication

Catalytic activityi

ATP + a protein = ADP + a phosphoprotein.
ATP + [DNA-directed RNA polymerase] = ADP + [DNA-directed RNA polymerase] phosphate.

Enzyme regulationi

Phosphorylation at Thr-14 or Tyr-15 inactivates the enzyme, while phosphorylation at Thr-161 activates it.By similarity

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei33 – 331ATPPROSITE-ProRule annotation
Active sitei128 – 1281Proton acceptorPROSITE-ProRule annotation

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi10 – 189ATPPROSITE-ProRule annotation

GO - Molecular functioni

  • ATP binding Source: UniProtKB-KW
  • cyclin-dependent protein serine/threonine kinase activity Source: FlyBase
  • protein kinase activity Source: FlyBase
  • protein serine/threonine kinase activity Source: FlyBase
  • RNA polymerase II carboxy-terminal domain kinase activity Source: UniProtKB-EC

GO - Biological processi

  • asymmetric neuroblast division Source: FlyBase
  • cellular response to DNA damage stimulus Source: FlyBase
  • G1/S transition of mitotic cell cycle Source: FlyBase
  • G2/M transition of mitotic cell cycle Source: FlyBase
  • germarium-derived cystoblast division Source: FlyBase
  • male meiosis Source: FlyBase
  • male meiosis I Source: FlyBase
  • meiotic G2/MI transition Source: FlyBase
  • mitotic cell cycle Source: FlyBase
  • mitotic G2/M transition checkpoint Source: FlyBase
  • mitotic G2 DNA damage checkpoint Source: FlyBase
  • mitotic nuclear division Source: UniProtKB-KW
  • neurogenesis Source: FlyBase
  • protein phosphorylation Source: FlyBase
  • regulation of protein localization Source: FlyBase
  • spermatogenesis Source: FlyBase
  • spermatogonial cell division Source: FlyBase
Complete GO annotation...

Keywords - Molecular functioni

Kinase, Serine/threonine-protein kinase, Transferase

Keywords - Biological processi

Cell cycle, Cell division, Mitosis

Keywords - Ligandi

ATP-binding, Nucleotide-binding

Enzyme and pathway databases

ReactomeiREACT_276179. Cyclin A/B1 associated events during G2/M transition.
REACT_282432. G1/S-Specific Transcription.
REACT_283248. MASTL Facilitates Mitotic Progression.
REACT_284729. Depolymerisation of the Nuclear Lamina.
REACT_286636. Regulation of APC/C activators between G1/S and early anaphase.
REACT_287862. Nuclear Pore Complex (NPC) Disassembly.
REACT_299649. Resolution of Sister Chromatid Cohesion.
REACT_301564. Golgi Cisternae Pericentriolar Stack Reorganization.
REACT_317616. E2F-enabled inhibition of pre-replication complex formation.
REACT_318147. G0 and Early G1.
REACT_318689. G2/M DNA replication checkpoint.
REACT_319950. Chk1/Chk2(Cds1) mediated inactivation of Cyclin B:Cdk1 complex.
REACT_321324. APC/C:Cdc20 mediated degradation of Cyclin B.
REACT_324794. Condensation of Prometaphase Chromosomes.
REACT_331011. Phosphorylation of the APC/C.
REACT_335593. Cdc20:Phospho-APC/C mediated degradation of Cyclin A.
REACT_340065. Cyclin B2 mediated events.
REACT_345084. E2F mediated regulation of DNA replication.
REACT_353740. Activation of NIMA Kinases NEK9, NEK6, NEK7.
REACT_354208. ERK1 activation.
SignaLinkiP23572.

Names & Taxonomyi

Protein namesi
Recommended name:
Cyclin-dependent kinase 1 (EC:2.7.11.22, EC:2.7.11.23)
Short name:
CDK1
Alternative name(s):
Cell division control protein 2 homolog
Cell division protein kinase 1
p34 protein kinase
Gene namesi
Name:cdc2
Synonyms:cdk1
ORF Names:CG5363
OrganismiDrosophila melanogaster (Fruit fly)
Taxonomic identifieri7227 [NCBI]
Taxonomic lineageiEukaryotaMetazoaEcdysozoaArthropodaHexapodaInsectaPterygotaNeopteraEndopterygotaDipteraBrachyceraMuscomorphaEphydroideaDrosophilidaeDrosophilaSophophora
ProteomesiUP000000803 Componenti: Chromosome 2L

Organism-specific databases

FlyBaseiFBgn0004106. cdc2.

Subcellular locationi

GO - Cellular componenti

  • microtubule associated complex Source: FlyBase
  • nucleus Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi43 – 431G → D in cdc2-E1-4; larval-pupal lethal with some adult escapers. 1 Publication
Mutagenesisi145 – 1451A → V in cdc2-216A; larval-pupal lethal. 2 Publications
Mutagenesisi148 – 1481G → R in cdc2-D57; embryonic or larval-pupal lethal. 2 Publications
Mutagenesisi176 – 1761L → Q in cdc2-E10; larval-pupal lethal. 1 Publication
Mutagenesisi196 – 1961E → K in cdc2-E1-24; larval-pupal lethal with some adult escapers. 2 Publications
Mutagenesisi206 – 2061G → D in cdc2-E1-23; larval-pupal lethal. 2 Publications
Mutagenesisi242 – 2421P → S in cdc2-E1-9; larval-pupal lethal. 2 Publications

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 297297Cyclin-dependent kinase 1PRO_0000085743Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei14 – 141Phosphothreonine1 Publication
Modified residuei15 – 151Phosphotyrosine1 Publication
Modified residuei160 – 1601Phosphotyrosine1 Publication
Modified residuei161 – 1611Phosphothreonine; by CAKSequence Analysis

Keywords - PTMi

Phosphoprotein

Proteomic databases

PaxDbiP23572.
PRIDEiP23572.

Expressioni

Developmental stagei

Expressed both maternally and zygotically.2 Publications

Gene expression databases

BgeeiP23572.
ExpressionAtlasiP23572. differential.
GenevisibleiP23572. DM.

Interactioni

Subunit structurei

Forms a stable but non-covalent complex with a regulatory subunit and with a cyclin.

Binary interactionsi

WithEntry#Exp.IntActNotes
Cks85AQ9VHN14EBI-108689,EBI-122930
CycB3Q9I7I02EBI-108689,EBI-150964
CycCP250084EBI-108689,EBI-195485
CycEP547336EBI-108689,EBI-203549
CycKQ961D14EBI-108689,EBI-130995
tweQ030194EBI-108689,EBI-138996

Protein-protein interaction databases

BioGridi60495. 38 interactions.
DIPiDIP-649N.
IntActiP23572. 25 interactions.
MINTiMINT-292976.

Structurei

3D structure databases

ProteinModelPortaliP23572.
SMRiP23572. Positions 1-287.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini4 – 287284Protein kinasePROSITE-ProRule annotationAdd
BLAST

Sequence similaritiesi

Contains 1 protein kinase domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiCOG0515.
GeneTreeiENSGT00790000122973.
InParanoidiP23572.
KOiK02087.
OMAiIMEDAGL.
OrthoDBiEOG7966H8.
PhylomeDBiP23572.

Family and domain databases

InterProiIPR011009. Kinase-like_dom.
IPR000719. Prot_kinase_dom.
IPR017441. Protein_kinase_ATP_BS.
IPR002290. Ser/Thr_dual-sp_kinase.
IPR008271. Ser/Thr_kinase_AS.
[Graphical view]
PfamiPF00069. Pkinase. 1 hit.
[Graphical view]
SMARTiSM00220. S_TKc. 1 hit.
[Graphical view]
SUPFAMiSSF56112. SSF56112. 1 hit.
PROSITEiPS00107. PROTEIN_KINASE_ATP. 1 hit.
PS50011. PROTEIN_KINASE_DOM. 1 hit.
PS00108. PROTEIN_KINASE_ST. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P23572-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MEDFEKIEKI GEGTYGVVYK GRNRLTGQIV AMKKIRLESD DEGVPSTAIR
60 70 80 90 100
EISLLKELKH ENIVCLEDVL MEENRIYLIF EFLSMDLKKY MDSLPVDKHM
110 120 130 140 150
ESELVRSYLY QITSAILFCH RRRVLHRDLK PQNLLIDKSG LIKVADFGLG
160 170 180 190 200
RSFGIPVRIY THEIVTLWYR APEVLLGSPR YSCPVDIWSI GCIFAEMATR
210 220 230 240 250
KPLFQGDSEI DQLFRMFRIL KTPTEDIWPG VTSLPDYKNT FPCWSTNQLT
260 270 280 290
NQLKNLDANG IDLIQKMLIY DPVHRISAKD ILEHPYFNGF QSGLVRN
Length:297
Mass (Da):34,439
Last modified:November 1, 1991 - v1
Checksum:i952CF136D8AB64C0
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X57485 mRNA. Translation: CAA40723.1.
X57496 mRNA. Translation: CAA40733.1.
S66801 Genomic DNA. Translation: AAP13986.1.
S66804 Genomic DNA. Translation: AAP13987.1.
S66805 Genomic DNA. Translation: AAP13988.1.
S66807 Genomic DNA. Translation: AAP13989.1.
S66810 Genomic DNA. Translation: AAP13990.1.
AM294319 Genomic DNA. Translation: CAL26249.1.
AM294320 Genomic DNA. Translation: CAL26250.1.
AM294321 Genomic DNA. Translation: CAL26251.1.
AM294322 Genomic DNA. Translation: CAL26252.1.
AM294323 Genomic DNA. Translation: CAL26253.1.
AM294324 Genomic DNA. Translation: CAL26254.1.
AM294325 Genomic DNA. Translation: CAL26255.1.
AM294326 Genomic DNA. Translation: CAL26256.1.
AM294327 Genomic DNA. Translation: CAL26257.1.
AM294328 Genomic DNA. Translation: CAL26258.1.
AM294329 Genomic DNA. Translation: CAL26259.1.
AE014134 Genomic DNA. Translation: AAF52932.1.
AY061450 mRNA. Translation: AAL28998.1.
PIRiS12009.
RefSeqiNP_476797.1. NM_057449.4.
UniGeneiDm.3187.

Genome annotation databases

EnsemblMetazoaiFBtr0080051; FBpp0079641; FBgn0004106.
GeneIDi34411.
KEGGidme:Dmel_CG5363.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X57485 mRNA. Translation: CAA40723.1.
X57496 mRNA. Translation: CAA40733.1.
S66801 Genomic DNA. Translation: AAP13986.1.
S66804 Genomic DNA. Translation: AAP13987.1.
S66805 Genomic DNA. Translation: AAP13988.1.
S66807 Genomic DNA. Translation: AAP13989.1.
S66810 Genomic DNA. Translation: AAP13990.1.
AM294319 Genomic DNA. Translation: CAL26249.1.
AM294320 Genomic DNA. Translation: CAL26250.1.
AM294321 Genomic DNA. Translation: CAL26251.1.
AM294322 Genomic DNA. Translation: CAL26252.1.
AM294323 Genomic DNA. Translation: CAL26253.1.
AM294324 Genomic DNA. Translation: CAL26254.1.
AM294325 Genomic DNA. Translation: CAL26255.1.
AM294326 Genomic DNA. Translation: CAL26256.1.
AM294327 Genomic DNA. Translation: CAL26257.1.
AM294328 Genomic DNA. Translation: CAL26258.1.
AM294329 Genomic DNA. Translation: CAL26259.1.
AE014134 Genomic DNA. Translation: AAF52932.1.
AY061450 mRNA. Translation: AAL28998.1.
PIRiS12009.
RefSeqiNP_476797.1. NM_057449.4.
UniGeneiDm.3187.

3D structure databases

ProteinModelPortaliP23572.
SMRiP23572. Positions 1-287.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi60495. 38 interactions.
DIPiDIP-649N.
IntActiP23572. 25 interactions.
MINTiMINT-292976.

Proteomic databases

PaxDbiP23572.
PRIDEiP23572.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblMetazoaiFBtr0080051; FBpp0079641; FBgn0004106.
GeneIDi34411.
KEGGidme:Dmel_CG5363.

Organism-specific databases

CTDi34411.
FlyBaseiFBgn0004106. cdc2.

Phylogenomic databases

eggNOGiCOG0515.
GeneTreeiENSGT00790000122973.
InParanoidiP23572.
KOiK02087.
OMAiIMEDAGL.
OrthoDBiEOG7966H8.
PhylomeDBiP23572.

Enzyme and pathway databases

ReactomeiREACT_276179. Cyclin A/B1 associated events during G2/M transition.
REACT_282432. G1/S-Specific Transcription.
REACT_283248. MASTL Facilitates Mitotic Progression.
REACT_284729. Depolymerisation of the Nuclear Lamina.
REACT_286636. Regulation of APC/C activators between G1/S and early anaphase.
REACT_287862. Nuclear Pore Complex (NPC) Disassembly.
REACT_299649. Resolution of Sister Chromatid Cohesion.
REACT_301564. Golgi Cisternae Pericentriolar Stack Reorganization.
REACT_317616. E2F-enabled inhibition of pre-replication complex formation.
REACT_318147. G0 and Early G1.
REACT_318689. G2/M DNA replication checkpoint.
REACT_319950. Chk1/Chk2(Cds1) mediated inactivation of Cyclin B:Cdk1 complex.
REACT_321324. APC/C:Cdc20 mediated degradation of Cyclin B.
REACT_324794. Condensation of Prometaphase Chromosomes.
REACT_331011. Phosphorylation of the APC/C.
REACT_335593. Cdc20:Phospho-APC/C mediated degradation of Cyclin A.
REACT_340065. Cyclin B2 mediated events.
REACT_345084. E2F mediated regulation of DNA replication.
REACT_353740. Activation of NIMA Kinases NEK9, NEK6, NEK7.
REACT_354208. ERK1 activation.
SignaLinkiP23572.

Miscellaneous databases

GenomeRNAii34411.
NextBioi788369.
PROiP23572.

Gene expression databases

BgeeiP23572.
ExpressionAtlasiP23572. differential.
GenevisibleiP23572. DM.

Family and domain databases

InterProiIPR011009. Kinase-like_dom.
IPR000719. Prot_kinase_dom.
IPR017441. Protein_kinase_ATP_BS.
IPR002290. Ser/Thr_dual-sp_kinase.
IPR008271. Ser/Thr_kinase_AS.
[Graphical view]
PfamiPF00069. Pkinase. 1 hit.
[Graphical view]
SMARTiSM00220. S_TKc. 1 hit.
[Graphical view]
SUPFAMiSSF56112. SSF56112. 1 hit.
PROSITEiPS00107. PROTEIN_KINASE_ATP. 1 hit.
PS50011. PROTEIN_KINASE_DOM. 1 hit.
PS00108. PROTEIN_KINASE_ST. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Drosophila cdc2 homologs: a functional homolog is coexpressed with a cognate variant."
    Lehner C.F., O'Farrell P.H.
    EMBO J. 9:3573-3581(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  2. "Complementation of fission yeast cdc2ts and cdc25ts mutants identifies two cell cycle genes from Drosophila: a cdc2 homologue and string."
    Jimenez J., Alphey L., Nurse P., Glover D.M.
    EMBO J. 9:3565-3571(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, DEVELOPMENTAL STAGE.
  3. "Genetic analysis of the Drosophila cdc2 homolog."
    Stern B., Ried G., Clegg N.J., Grigliatti T.A., Lehner C.F.
    Development 117:219-232(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], MUTAGENESIS OF ALA-145; GLY-148; GLU-196; GLY-206 AND PRO-242.
  4. "Widespread adaptive evolution of Drosophila genes with sex-biased expression."
    Proeschel M., Zhang Z., Parsch J.
    Genetics 174:893-900(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    Strain: ZBMEL131, ZBMEL145, ZBMEL157, ZBMEL186, ZBMEL229, ZBMEL377, ZBMEL384, ZBMEL398, ZBMEL82, ZBMEL84 and ZBMEL95.
  5. "The genome sequence of Drosophila melanogaster."
    Adams M.D., Celniker S.E., Holt R.A., Evans C.A., Gocayne J.D., Amanatides P.G., Scherer S.E., Li P.W., Hoskins R.A., Galle R.F., George R.A., Lewis S.E., Richards S., Ashburner M., Henderson S.N., Sutton G.G., Wortman J.R., Yandell M.D.
    , Zhang Q., Chen L.X., Brandon R.C., Rogers Y.-H.C., Blazej R.G., Champe M., Pfeiffer B.D., Wan K.H., Doyle C., Baxter E.G., Helt G., Nelson C.R., Miklos G.L.G., Abril J.F., Agbayani A., An H.-J., Andrews-Pfannkoch C., Baldwin D., Ballew R.M., Basu A., Baxendale J., Bayraktaroglu L., Beasley E.M., Beeson K.Y., Benos P.V., Berman B.P., Bhandari D., Bolshakov S., Borkova D., Botchan M.R., Bouck J., Brokstein P., Brottier P., Burtis K.C., Busam D.A., Butler H., Cadieu E., Center A., Chandra I., Cherry J.M., Cawley S., Dahlke C., Davenport L.B., Davies P., de Pablos B., Delcher A., Deng Z., Mays A.D., Dew I., Dietz S.M., Dodson K., Doup L.E., Downes M., Dugan-Rocha S., Dunkov B.C., Dunn P., Durbin K.J., Evangelista C.C., Ferraz C., Ferriera S., Fleischmann W., Fosler C., Gabrielian A.E., Garg N.S., Gelbart W.M., Glasser K., Glodek A., Gong F., Gorrell J.H., Gu Z., Guan P., Harris M., Harris N.L., Harvey D.A., Heiman T.J., Hernandez J.R., Houck J., Hostin D., Houston K.A., Howland T.J., Wei M.-H., Ibegwam C., Jalali M., Kalush F., Karpen G.H., Ke Z., Kennison J.A., Ketchum K.A., Kimmel B.E., Kodira C.D., Kraft C.L., Kravitz S., Kulp D., Lai Z., Lasko P., Lei Y., Levitsky A.A., Li J.H., Li Z., Liang Y., Lin X., Liu X., Mattei B., McIntosh T.C., McLeod M.P., McPherson D., Merkulov G., Milshina N.V., Mobarry C., Morris J., Moshrefi A., Mount S.M., Moy M., Murphy B., Murphy L., Muzny D.M., Nelson D.L., Nelson D.R., Nelson K.A., Nixon K., Nusskern D.R., Pacleb J.M., Palazzolo M., Pittman G.S., Pan S., Pollard J., Puri V., Reese M.G., Reinert K., Remington K., Saunders R.D.C., Scheeler F., Shen H., Shue B.C., Siden-Kiamos I., Simpson M., Skupski M.P., Smith T.J., Spier E., Spradling A.C., Stapleton M., Strong R., Sun E., Svirskas R., Tector C., Turner R., Venter E., Wang A.H., Wang X., Wang Z.-Y., Wassarman D.A., Weinstock G.M., Weissenbach J., Williams S.M., Woodage T., Worley K.C., Wu D., Yang S., Yao Q.A., Ye J., Yeh R.-F., Zaveri J.S., Zhan M., Zhang G., Zhao Q., Zheng L., Zheng X.H., Zhong F.N., Zhong W., Zhou X., Zhu S.C., Zhu X., Smith H.O., Gibbs R.A., Myers E.W., Rubin G.M., Venter J.C.
    Science 287:2185-2195(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: Berkeley.
  6. Cited for: GENOME REANNOTATION.
    Strain: Berkeley.
  7. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Strain: Berkeley.
  8. "A developmental and molecular analysis of cdc2 mutations in Drosophila melanogaster."
    Clegg N.J., Whitehead I.P., Williams J.A., Spiegelman G.B., Grigliatti T.A.
    Genome 36:676-685(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF GLY-43; ALA-145; GLY-148; LEU-176; GLU-196; GLY-206 AND PRO-242, DEVELOPMENTAL STAGE.
  9. "Phosphoproteome analysis of Drosophila melanogaster embryos."
    Zhai B., Villen J., Beausoleil S.A., Mintseris J., Gygi S.P.
    J. Proteome Res. 7:1675-1682(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT THR-14; TYR-15; TYR-160 AND THR-161, IDENTIFICATION BY MASS SPECTROMETRY.
    Tissue: Embryo.

Entry informationi

Entry nameiCDK1_DROME
AccessioniPrimary (citable) accession number: P23572
Secondary accession number(s): A0ANT1
, Q86FT5, Q86FT6, Q86FT7, Q86FT8, Q86FT9, Q9TX68, Q9TX69, Q9TX70, Q9TX71, Q9TX72, Q9TX73, Q9TX74, Q9VKX5
Entry historyi
Integrated into UniProtKB/Swiss-Prot: November 1, 1991
Last sequence update: November 1, 1991
Last modified: June 24, 2015
This is version 166 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programDrosophila annotation project

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. Drosophila
    Drosophila: entries, gene names and cross-references to FlyBase
  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.