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Protein

Ancient ubiquitous protein 1

Gene

AUP1

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

May play a role in the translocation of terminally misfolded proteins from the endoplasmic reticulum lumen to the cytoplasm and their degradation by the proteasome.1 Publication

GO - Biological processi

  • retrograde protein transport, ER to cytosol Source: ParkinsonsUK-UCL
Complete GO annotation...

Keywords - Biological processi

Ubl conjugation pathway

Names & Taxonomyi

Protein namesi
Recommended name:
Ancient ubiquitous protein 1
Gene namesi
Name:AUP1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 2

Organism-specific databases

HGNCiHGNC:891. AUP1.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 2020LumenalSequence AnalysisAdd
BLAST
Transmembranei21 – 4121Helical; Signal-anchor for type III membrane proteinSequence AnalysisAdd
BLAST
Topological domaini42 – 476435CytoplasmicSequence AnalysisAdd
BLAST

GO - Cellular componenti

  • endoplasmic reticulum membrane Source: UniProtKB-SubCell
  • extracellular exosome Source: UniProtKB
  • integral component of membrane Source: UniProtKB-KW
  • membrane Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Endoplasmic reticulum, Membrane

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA25182.

Polymorphism and mutation databases

BioMutaiAUP1.
DMDMi12643958.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 476476Ancient ubiquitous protein 1PRO_0000020765Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei1 – 11N-acetylmethionine2 Publications
Modified residuei354 – 3541Phosphoserine3 Publications
Modified residuei358 – 3581Phosphoserine1 Publication
Modified residuei429 – 4291Phosphoserine1 Publication
Modified residuei433 – 4331Phosphothreonine2 Publications

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiQ9Y679.
PaxDbiQ9Y679.
PRIDEiQ9Y679.

PTM databases

PhosphoSiteiQ9Y679.

Expressioni

Tissue specificityi

Detected in blood platelets and leukocytes (at protein level). Ubiquitous. Highly expressed in placenta, liver, kidney, skeletal muscle, heart and brain.1 Publication

Gene expression databases

BgeeiQ9Y679.
CleanExiHS_AUP1.
GenevisibleiQ9Y679. HS.

Organism-specific databases

HPAiHPA007674.

Interactioni

Subunit structurei

Identified in a complex that contains SEL1L, OS9, FAF2/UBXD8, UBE2J1/UBC6E and AUP1. Interacts with the cytoplasmic tail of ITGA2B, ITGA1, ITGA2, ITGA5, ITGAV and ITGAM.2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
OPRM1P353724EBI-1058701,EBI-2624570

Protein-protein interaction databases

BioGridi107031. 47 interactions.
IntActiQ9Y679. 11 interactions.
MINTiMINT-1190912.
STRINGi9606.ENSP00000366748.

Structurei

Secondary structure

1
476
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi363 – 37311Combined sources
Beta strandi375 – 3773Combined sources
Helixi379 – 3879Combined sources
Helixi392 – 4009Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2EKFNMR-A358-411[»]
ProteinModelPortaliQ9Y679.
SMRiQ9Y679. Positions 359-411.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ9Y679.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini362 – 40443CUEPROSITE-ProRule annotationAdd
BLAST

Compositional bias

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Compositional biasi160 – 1656Poly-Phe

Sequence similaritiesi

Belongs to the AUP1 family.Curated
Contains 1 CUE domain.PROSITE-ProRule annotation

Keywords - Domaini

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG271344.
GeneTreeiENSGT00390000016110.
HOGENOMiHOG000034232.
HOVERGENiHBG004321.
InParanoidiQ9Y679.
OMAiLGIHVFL.
OrthoDBiEOG7HTHHJ.
PhylomeDBiQ9Y679.
TreeFamiTF313372.

Family and domain databases

InterProiIPR003892. CUE.
[Graphical view]
PfamiPF02845. CUE. 1 hit.
[Graphical view]
SMARTiSM00546. CUE. 1 hit.
[Graphical view]
PROSITEiPS51140. CUE. 1 hit.
[Graphical view]

Sequences (3)i

Sequence statusi: Complete.

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

Isoform Long (identifier: Q9Y679-1) [UniParc]FASTAAdd to basket

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
MELPSGPGPE RLFDSHRLPG DCFLLLVLLL YAPVGFCLLV LRLFLGIHVF
60 70 80 90 100
LVSCALPDSV LRRFVVRTMC AVLGLVARQE DSGLRDHSVR VLISNHVTPF
110 120 130 140 150
DHNIVNLLTT CSTVSESEAE SATGRFPGAQ LKAPLSPLAF RMEDTEALPL
160 170 180 190 200
TPILYPTCQF FFFIFLNIFL LAFSSPGSQP LLNSPPSFVC WSRGFMEMNG
210 220 230 240 250
RGELVESLKR FCASTRLPPT PLLLFPEEEA TNGREGLLRF SSWPFSIQDV
260 270 280 290 300
VQPLTLQVQR PLVSVTVSDA SWVSELLWSL FVPFTVYQVR WLRPVHRQLG
310 320 330 340 350
EANEEFALRV QQLVAKELGQ TGTRLTPADK AEHMKRQRHP RLRPQSAQSS
360 370 380 390 400
FPPSPGPSPD VQLATLAQRV KEVLPHVPLG VIQRDLAKTG CVDLTITNLL
410 420 430 440 450
EGAVAFMPED ITKGTQSLPT ASASKFPSSG PVTPQPTALT FAKSSWARQE
460 470
SLQERKQALY EYARRRFTER RAQEAD
Length:476
Mass (Da):53,028
Last modified:November 1, 1999 - v1
Checksum:iA6AF3AAD84AE86CB
GO
Isoform Short (identifier: Q9Y679-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     114-179: Missing.

Show »
Length:410
Mass (Da):45,787
Checksum:i1A06476225C5DFDC
GO
Isoform 3 (identifier: Q9Y679-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     114-179: Missing.
     426-439: FPSSGPVTPQPTAL → AFDACLMMMTPQAL
     440-476: Missing.

Show »
Length:373
Mass (Da):41,385
Checksum:iAAB256D01055538E
GO

Sequence cautioni

The sequence AAH33646.2 differs from that shown. Reason: Erroneous initiation. Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti354 – 3541S → P in AAD43010 (Ref. 3) Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei114 – 17966Missing in isoform Short and isoform 3. 5 PublicationsVSP_004133Add
BLAST
Alternative sequencei426 – 43914FPSSG…QPTAL → AFDACLMMMTPQAL in isoform 3. 1 PublicationVSP_036228Add
BLAST
Alternative sequencei440 – 47637Missing in isoform 3. 1 PublicationVSP_036229Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF100754 mRNA. Translation: AAD43018.1.
AF100753 mRNA. Translation: AAD43017.1.
AF100746 mRNA. Translation: AAD43010.1.
AF165515 mRNA. Translation: AAF86645.1.
AK023983 mRNA. Translation: BAB14753.1.
CH471053 Genomic DNA. Translation: EAW99623.1.
BC001658 mRNA. Translation: AAH01658.1.
BC033646 mRNA. Translation: AAH33646.2. Different initiation.
CCDSiCCDS42702.1. [Q9Y679-2]
RefSeqiNP_853553.1. NM_181575.4. [Q9Y679-2]
UniGeneiHs.411480.

Genome annotation databases

EnsembliENST00000377526; ENSP00000366748; ENSG00000115307. [Q9Y679-2]
ENST00000425118; ENSP00000403430; ENSG00000115307. [Q9Y679-3]
GeneIDi550.
KEGGihsa:550.
UCSCiuc002smf.3. human. [Q9Y679-2]
uc002smh.3. human. [Q9Y679-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF100754 mRNA. Translation: AAD43018.1.
AF100753 mRNA. Translation: AAD43017.1.
AF100746 mRNA. Translation: AAD43010.1.
AF165515 mRNA. Translation: AAF86645.1.
AK023983 mRNA. Translation: BAB14753.1.
CH471053 Genomic DNA. Translation: EAW99623.1.
BC001658 mRNA. Translation: AAH01658.1.
BC033646 mRNA. Translation: AAH33646.2. Different initiation.
CCDSiCCDS42702.1. [Q9Y679-2]
RefSeqiNP_853553.1. NM_181575.4. [Q9Y679-2]
UniGeneiHs.411480.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2EKFNMR-A358-411[»]
ProteinModelPortaliQ9Y679.
SMRiQ9Y679. Positions 359-411.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi107031. 47 interactions.
IntActiQ9Y679. 11 interactions.
MINTiMINT-1190912.
STRINGi9606.ENSP00000366748.

PTM databases

PhosphoSiteiQ9Y679.

Polymorphism and mutation databases

BioMutaiAUP1.
DMDMi12643958.

Proteomic databases

MaxQBiQ9Y679.
PaxDbiQ9Y679.
PRIDEiQ9Y679.

Protocols and materials databases

DNASUi550.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000377526; ENSP00000366748; ENSG00000115307. [Q9Y679-2]
ENST00000425118; ENSP00000403430; ENSG00000115307. [Q9Y679-3]
GeneIDi550.
KEGGihsa:550.
UCSCiuc002smf.3. human. [Q9Y679-2]
uc002smh.3. human. [Q9Y679-1]

Organism-specific databases

CTDi550.
GeneCardsiGC02M074753.
HGNCiHGNC:891. AUP1.
HPAiHPA007674.
MIMi602434. gene.
neXtProtiNX_Q9Y679.
PharmGKBiPA25182.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG271344.
GeneTreeiENSGT00390000016110.
HOGENOMiHOG000034232.
HOVERGENiHBG004321.
InParanoidiQ9Y679.
OMAiLGIHVFL.
OrthoDBiEOG7HTHHJ.
PhylomeDBiQ9Y679.
TreeFamiTF313372.

Miscellaneous databases

ChiTaRSiAUP1. human.
EvolutionaryTraceiQ9Y679.
GeneWikiiAUP1.
GenomeRNAii550.
NextBioi2273.
PROiQ9Y679.
SOURCEiSearch...

Gene expression databases

BgeeiQ9Y679.
CleanExiHS_AUP1.
GenevisibleiQ9Y679. HS.

Family and domain databases

InterProiIPR003892. CUE.
[Graphical view]
PfamiPF02845. CUE. 1 hit.
[Graphical view]
SMARTiSM00546. CUE. 1 hit.
[Graphical view]
PROSITEiPS51140. CUE. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Human ancient ubiquitous protein AUP1 isoform gene."
    Peng Y., Song H., Dai M., Huang Q., Mao Y., Zhang Q., Mao M., Fu G., Luo M., Chen J., Hu R.
    Submitted (OCT-1998) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS LONG AND SHORT).
    Tissue: Pituitary.
  2. "Cloning and functional analysis of cDNAs with open reading frames for 300 previously undefined genes expressed in CD34+ hematopoietic stem/progenitor cells."
    Zhang Q.-H., Ye M., Wu X.-Y., Ren S.-X., Zhao M., Zhao C.-J., Fu G., Shen Y., Fan H.-Y., Lu G., Zhong M., Xu X.-R., Han Z.-G., Zhang J.-W., Tao J., Huang Q.-H., Zhou J., Hu G.-X.
    , Gu J., Chen S.-J., Chen Z.
    Genome Res. 10:1546-1560(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM SHORT).
    Tissue: Umbilical cord blood.
  3. "Novel genes expressed in hematopoietic stem/progenitor cells from myelodysplastic syndrome patients."
    Gu J., Huang Q., Yu Y., Xu S., Han Z., Fu G., Zhou J., Wang Y., Huang C., Ren S., Tu Y., Chen Z.
    Submitted (JUL-1999) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM SHORT).
    Tissue: Hematopoietic stem cell.
  4. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM SHORT).
    Tissue: Eye.
  5. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  6. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
    The MGC Project Team
    Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 3 AND SHORT).
    Tissue: Eye and Skin.
  7. "Ancient ubiquitous protein 1 binds to the conserved membrane-proximal sequence of the cytoplasmic tail of the integrin alpha subunits that plays a crucial role in the inside-out signaling of alpha IIbbeta 3."
    Kato A., Kawamata N., Tamayose K., Egashira M., Miura R., Fujimura T., Murayama K., Oshimi K.
    J. Biol. Chem. 277:28934-28941(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: SUBCELLULAR LOCATION, INTERACTION WITH ITGA2B; ITGA1; ITGA2; ITGA5; ITGAV AND ITGAM, TISSUE SPECIFICITY.
  8. "Kinase-selective enrichment enables quantitative phosphoproteomics of the kinome across the cell cycle."
    Daub H., Olsen J.V., Bairlein M., Gnad F., Oppermann F.S., Korner R., Greff Z., Keri G., Stemmann O., Mann M.
    Mol. Cell 31:438-448(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-354 AND THR-433, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  9. Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-354; SER-358; SER-429 AND THR-433, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  10. "SEL1L nucleates a protein complex required for dislocation of misfolded glycoproteins."
    Mueller B., Klemm E.J., Spooner E., Claessen J.H., Ploegh H.L.
    Proc. Natl. Acad. Sci. U.S.A. 105:12325-12330(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION IN A COMPLEX WITH SEL1L, SUBCELLULAR LOCATION, FUNCTION.
  11. "Lys-N and trypsin cover complementary parts of the phosphoproteome in a refined SCX-based approach."
    Gauci S., Helbig A.O., Slijper M., Krijgsveld J., Heck A.J., Mohammed S.
    Anal. Chem. 81:4493-4501(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  12. "Quantitative phosphoproteomics reveals widespread full phosphorylation site occupancy during mitosis."
    Olsen J.V., Vermeulen M., Santamaria A., Kumar C., Miller M.L., Jensen L.J., Gnad F., Cox J., Jensen T.S., Nigg E.A., Brunak S., Mann M.
    Sci. Signal. 3:RA3-RA3(2010) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-354, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  13. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  14. "Comparative large-scale characterisation of plant vs. mammal proteins reveals similar and idiosyncratic N-alpha acetylation features."
    Bienvenut W.V., Sumpton D., Martinez A., Lilla S., Espagne C., Meinnel T., Giglione C.
    Mol. Cell. Proteomics 11:M111.015131-M111.015131(2012) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  15. Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  16. "Solution structure of RSGI RUH-075, a human CUE domain."
    RIKEN structural genomics initiative (RSGI)
    Submitted (SEP-2007) to the PDB data bank
    Cited for: STRUCTURE BY NMR OF 358-411.

Entry informationi

Entry nameiAUP1_HUMAN
AccessioniPrimary (citable) accession number: Q9Y679
Secondary accession number(s): C0H5W8
, Q9H866, Q9UNQ6, Q9Y685
Entry historyi
Integrated into UniProtKB/Swiss-Prot: December 1, 2000
Last sequence update: November 1, 1999
Last modified: July 22, 2015
This is version 127 of the entry and version 1 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

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 2
    Human chromosome 2: entries, gene names and cross-references to MIM
  2. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  3. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  4. 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.