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Protein

Transcriptional adapter ADA2b

Gene

ADA2B

Organism
Arabidopsis thaliana (Mouse-ear cress)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Required for the function of some acidic activation domains, which activate transcription from a distant site. The exact mechanism of action is not yet known (By similarity). ADA2 stimulates the acetyltransferase activity of GCN5 on free histones or nucleosomes, probably by opening up the promoter region. Mediates auxin and cytokinin signals in the control of cell proliferation and might be involved in repression of a freezing tolerance pathway at warm temperature.By similarity2 Publications

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri41 – 8848ZZ-typePROSITE-ProRule annotationAdd
BLAST

GO - Molecular functioni

GO - Biological processi

  • chromatin remodeling Source: GO_Central
  • cold acclimation Source: TAIR
  • histone acetylation Source: GOC
  • positive regulation of histone acetylation Source: GO_Central
  • regulation of cell proliferation Source: TAIR
  • regulation of transcription from RNA polymerase II promoter Source: GO_Central
  • response to auxin Source: TAIR
  • response to cytokinin Source: TAIR
  • transcription, DNA-templated Source: UniProtKB-KW
Complete GO annotation...

Keywords - Biological processi

Transcription, Transcription regulation

Keywords - Ligandi

DNA-binding, Metal-binding, Zinc

Names & Taxonomyi

Protein namesi
Recommended name:
Transcriptional adapter ADA2b
Short name:
AtADA2b
Alternative name(s):
Protein PROPORZ 1
Gene namesi
Name:ADA2B
Synonyms:PRZ1
Ordered Locus Names:At4g16420
ORF Names:dl4235c
OrganismiArabidopsis thaliana (Mouse-ear cress)
Taxonomic identifieri3702 [NCBI]
Taxonomic lineageiEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsmalvidsBrassicalesBrassicaceaeCamelineaeArabidopsis
Proteomesi
  • UP000006548 Componenti: Chromosome 4

Organism-specific databases

TAIRiAT4G16420.

Subcellular locationi

  • Nucleus PROSITE-ProRule annotation1 Publication

GO - Cellular componenti

  • nucleus Source: TAIR
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Disruption phenotypei

Plants have pleiotropic effects on plant growth and development, including dwarf size, aberrant root development, and short petals and stamens in flowers. ADA2a cannot rescue any of the mutant phenotypes.2 Publications

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi216 – 2161K → A or R: No phenotypic effect. 1 Publication

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 487487Transcriptional adapter ADA2bPRO_0000269751Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei216 – 2161N6-acetyllysine; by GCN51 Publication

Post-translational modificationi

Acetylated in vitro by GCN5, but acetylation is not essential for biological activity.1 Publication

Keywords - PTMi

Acetylation

Proteomic databases

PaxDbiQ9ATB4.
PRIDEiQ9ATB4.

PTM databases

iPTMnetiQ9ATB4.

Expressioni

Tissue specificityi

Expressed in roots, leaves, stems, flowers and siliques, with the strongest activity in the meristematic zones.2 Publications

Gene expression databases

GenevisibleiQ9ATB4. AT.

Interactioni

Subunit structurei

Interacts in vitro with the HAT domain of GCN5 and with the DNA-binding domain of the transcriptional activator DREB1B/CBF1.2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
HAG1Q9AR195EBI-979237,EBI-979271

Protein-protein interaction databases

BioGridi12629. 5 interactions.
IntActiQ9ATB4. 2 interactions.
STRINGi3702.AT4G16420.1.

Structurei

3D structure databases

ProteinModelPortaliQ9ATB4.
SMRiQ9ATB4. Positions 104-149, 420-479.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini100 – 15253SANTPROSITE-ProRule annotationAdd
BLAST
Domaini401 – 48787SWIRMPROSITE-ProRule annotationAdd
BLAST

Domaini

The middle domain of ADA2b is sufficient for interaction with the HAT catalytic domain of GCN5.

Sequence similaritiesi

Contains 1 SANT domain.PROSITE-ProRule annotation
Contains 1 SWIRM domain.PROSITE-ProRule annotation
Contains 1 ZZ-type zinc finger.PROSITE-ProRule annotation

Zinc finger

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri41 – 8848ZZ-typePROSITE-ProRule annotationAdd
BLAST

Keywords - Domaini

Zinc-finger

Phylogenomic databases

eggNOGiKOG0457. Eukaryota.
COG5114. LUCA.
HOGENOMiHOG000163455.
InParanoidiQ9ATB4.
KOiK11314.
OMAiRIRCADK.
PhylomeDBiQ9ATB4.

Family and domain databases

Gene3Di1.10.10.60. 1 hit.
InterProiIPR009057. Homeodomain-like.
IPR001005. SANT/Myb.
IPR017884. SANT_dom.
IPR007526. SWIRM.
IPR000433. Znf_ZZ.
[Graphical view]
PfamiPF00249. Myb_DNA-binding. 1 hit.
PF00569. ZZ. 1 hit.
[Graphical view]
SMARTiSM00717. SANT. 1 hit.
SM00291. ZnF_ZZ. 1 hit.
[Graphical view]
SUPFAMiSSF46689. SSF46689. 2 hits.
PROSITEiPS51293. SANT. 1 hit.
PS50934. SWIRM. 1 hit.
PS01357. ZF_ZZ_1. 1 hit.
PS50135. ZF_ZZ_2. 1 hit.
[Graphical view]

Sequences (3)i

Sequence statusi: Complete.

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

Isoform 1 (identifier: Q9ATB4-1) [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
MGRSRGNFQN FEDPTQRTRK KKNAANVENF ESTSLVPGAE GGGKYNCDYC
60 70 80 90 100
QKDITGKIRI KCAVCPDFDL CIECMSVGAE ITPHKCDHPY RVMGNLTFPL
110 120 130 140 150
ICPDWSADDE MLLLEGLEIY GLGNWAEVAE HVGTKSKEQC LEHYRNIYLN
160 170 180 190 200
SPFFPLPDMS HVAGKNRKEL QAMAKGRIDD KKAEQNMKEE YPFSPPKVKV
210 220 230 240 250
EDTQKESFVD RSFGGKKPVS TSVNNSLVEL SNYNQKREEF DPEYDNDAEQ
260 270 280 290 300
LLAEMEFKEN DTPEEHELKL RVLRIYSKRL DERKRRKEFI IERNLLYPNP
310 320 330 340 350
FEKDLSQEEK VQCRRLDVFM RFHSKEEHDE LLRNVVSEYR MVKRLKDLKE
360 370 380 390 400
AQVAGCRSTA EAERYLGRKR KRENEEGMNR GKESGQFGQI AGEMGSRPPV
410 420 430 440 450
QASSSYVNDL DLIGFTESQL LSESEKRLCS EVKLVPPVYL QMQQVMSHEI
460 470 480
FKGNVTKKSD AYSLFKIDPT KVDRVYDMLV KKGIAQL
Length:487
Mass (Da):56,186
Last modified:June 1, 2001 - v1
Checksum:i51914B5A31724CDC
GO
Isoform 2 (identifier: Q9ATB4-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     206-209: Missing.

Note: Derived from EST data. No experimental confirmation available.
Show »
Length:483
Mass (Da):55,723
Checksum:i1345D5FFC915CAF7
GO
Isoform 3 (identifier: Q9ATB4-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     183-183: Missing.

Note: Derived from EST data. No experimental confirmation available.
Show »
Length:486
Mass (Da):56,115
Checksum:i601194DE28A66019
GO

Sequence cautioni

The sequence CAB10418.1 differs from that shown. Reason: Erroneous gene model prediction. Curated
The sequence CAB78684.1 differs from that shown. Reason: Erroneous gene model prediction. Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei183 – 1831Missing in isoform 3. 1 PublicationVSP_022095
Alternative sequencei206 – 2094Missing in isoform 2. 1 PublicationVSP_022096

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF338770 mRNA. Translation: AAK31320.1.
Z97341 Genomic DNA. Translation: CAB10418.1. Sequence problems.
AL161544 Genomic DNA. Translation: CAB78684.1. Sequence problems.
CP002687 Genomic DNA. Translation: AEE83744.1.
CP002687 Genomic DNA. Translation: AEE83745.1.
CP002687 Genomic DNA. Translation: AEE83746.1.
AY143911 mRNA. Translation: AAN28850.1.
AY050348 mRNA. Translation: AAK91365.1.
BX827435 mRNA. No translation available.
BX827480 mRNA. No translation available.
PIRiH71430.
RefSeqiNP_567495.1. NM_117737.4. [Q9ATB4-1]
NP_974560.1. NM_202831.2. [Q9ATB4-2]
NP_974561.1. NM_202832.2. [Q9ATB4-3]
UniGeneiAt.4412.
At.71096.
At.72978.

Genome annotation databases

EnsemblPlantsiAT4G16420.1; AT4G16420.1; AT4G16420. [Q9ATB4-1]
GeneIDi827336.
KEGGiath:AT4G16420.

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF338770 mRNA. Translation: AAK31320.1.
Z97341 Genomic DNA. Translation: CAB10418.1. Sequence problems.
AL161544 Genomic DNA. Translation: CAB78684.1. Sequence problems.
CP002687 Genomic DNA. Translation: AEE83744.1.
CP002687 Genomic DNA. Translation: AEE83745.1.
CP002687 Genomic DNA. Translation: AEE83746.1.
AY143911 mRNA. Translation: AAN28850.1.
AY050348 mRNA. Translation: AAK91365.1.
BX827435 mRNA. No translation available.
BX827480 mRNA. No translation available.
PIRiH71430.
RefSeqiNP_567495.1. NM_117737.4. [Q9ATB4-1]
NP_974560.1. NM_202831.2. [Q9ATB4-2]
NP_974561.1. NM_202832.2. [Q9ATB4-3]
UniGeneiAt.4412.
At.71096.
At.72978.

3D structure databases

ProteinModelPortaliQ9ATB4.
SMRiQ9ATB4. Positions 104-149, 420-479.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi12629. 5 interactions.
IntActiQ9ATB4. 2 interactions.
STRINGi3702.AT4G16420.1.

PTM databases

iPTMnetiQ9ATB4.

Proteomic databases

PaxDbiQ9ATB4.
PRIDEiQ9ATB4.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblPlantsiAT4G16420.1; AT4G16420.1; AT4G16420. [Q9ATB4-1]
GeneIDi827336.
KEGGiath:AT4G16420.

Organism-specific databases

TAIRiAT4G16420.

Phylogenomic databases

eggNOGiKOG0457. Eukaryota.
COG5114. LUCA.
HOGENOMiHOG000163455.
InParanoidiQ9ATB4.
KOiK11314.
OMAiRIRCADK.
PhylomeDBiQ9ATB4.

Miscellaneous databases

PROiQ9ATB4.

Gene expression databases

GenevisibleiQ9ATB4. AT.

Family and domain databases

Gene3Di1.10.10.60. 1 hit.
InterProiIPR009057. Homeodomain-like.
IPR001005. SANT/Myb.
IPR017884. SANT_dom.
IPR007526. SWIRM.
IPR000433. Znf_ZZ.
[Graphical view]
PfamiPF00249. Myb_DNA-binding. 1 hit.
PF00569. ZZ. 1 hit.
[Graphical view]
SMARTiSM00717. SANT. 1 hit.
SM00291. ZnF_ZZ. 1 hit.
[Graphical view]
SUPFAMiSSF46689. SSF46689. 2 hits.
PROSITEiPS51293. SANT. 1 hit.
PS50934. SWIRM. 1 hit.
PS01357. ZF_ZZ_1. 1 hit.
PS50135. ZF_ZZ_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Transcriptional adaptor and histone acetyltransferase proteins in Arabidopsis and their interactions with CBF1, a transcriptional activator involved in cold-regulated gene expression."
    Stockinger E.J., Mao Y., Regier M.K., Triezenberg S.J., Thomashow M.F.
    Nucleic Acids Res. 29:1524-1533(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), IDENTIFICATION, TISSUE SPECIFICITY, INTERACTION WITH GCN5 AND DREB1B/CBF1.
  2. "Analysis of 1.9 Mb of contiguous sequence from chromosome 4 of Arabidopsis thaliana."
    Bevan M., Bancroft I., Bent E., Love K., Goodman H.M., Dean C., Bergkamp R., Dirkse W., van Staveren M., Stiekema W., Drost L., Ridley P., Hudson S.-A., Patel K., Murphy G., Piffanelli P., Wedler H., Wedler E.
    , Wambutt R., Weitzenegger T., Pohl T., Terryn N., Gielen J., Villarroel R., De Clercq R., van Montagu M., Lecharny A., Aubourg S., Gy I., Kreis M., Lao N., Kavanagh T., Hempel S., Kotter P., Entian K.-D., Rieger M., Schaefer M., Funk B., Mueller-Auer S., Silvey M., James R., Monfort A., Pons A., Puigdomenech P., Douka A., Voukelatou E., Milioni D., Hatzopoulos P., Piravandi E., Obermaier B., Hilbert H., Duesterhoeft A., Moores T., Jones J.D.G., Eneva T., Palme K., Benes V., Rechmann S., Ansorge W., Cooke R., Berger C., Delseny M., Voet M., Volckaert G., Mewes H.-W., Klosterman S., Schueller C., Chalwatzis N.
    Nature 391:485-488(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: cv. Columbia.
  3. "Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana."
    Mayer K.F.X., Schueller C., Wambutt R., Murphy G., Volckaert G., Pohl T., Duesterhoeft A., Stiekema W., Entian K.-D., Terryn N., Harris B., Ansorge W., Brandt P., Grivell L.A., Rieger M., Weichselgartner M., de Simone V., Obermaier B.
    , Mache R., Mueller M., Kreis M., Delseny M., Puigdomenech P., Watson M., Schmidtheini T., Reichert B., Portetelle D., Perez-Alonso M., Boutry M., Bancroft I., Vos P., Hoheisel J., Zimmermann W., Wedler H., Ridley P., Langham S.-A., McCullagh B., Bilham L., Robben J., van der Schueren J., Grymonprez B., Chuang Y.-J., Vandenbussche F., Braeken M., Weltjens I., Voet M., Bastiaens I., Aert R., Defoor E., Weitzenegger T., Bothe G., Ramsperger U., Hilbert H., Braun M., Holzer E., Brandt A., Peters S., van Staveren M., Dirkse W., Mooijman P., Klein Lankhorst R., Rose M., Hauf J., Koetter P., Berneiser S., Hempel S., Feldpausch M., Lamberth S., Van den Daele H., De Keyser A., Buysshaert C., Gielen J., Villarroel R., De Clercq R., van Montagu M., Rogers J., Cronin A., Quail M.A., Bray-Allen S., Clark L., Doggett J., Hall S., Kay M., Lennard N., McLay K., Mayes R., Pettett A., Rajandream M.A., Lyne M., Benes V., Rechmann S., Borkova D., Bloecker H., Scharfe M., Grimm M., Loehnert T.-H., Dose S., de Haan M., Maarse A.C., Schaefer M., Mueller-Auer S., Gabel C., Fuchs M., Fartmann B., Granderath K., Dauner D., Herzl A., Neumann S., Argiriou A., Vitale D., Liguori R., Piravandi E., Massenet O., Quigley F., Clabauld G., Muendlein A., Felber R., Schnabl S., Hiller R., Schmidt W., Lecharny A., Aubourg S., Chefdor F., Cooke R., Berger C., Monfort A., Casacuberta E., Gibbons T., Weber N., Vandenbol M., Bargues M., Terol J., Torres A., Perez-Perez A., Purnelle B., Bent E., Johnson S., Tacon D., Jesse T., Heijnen L., Schwarz S., Scholler P., Heber S., Francs P., Bielke C., Frishman D., Haase D., Lemcke K., Mewes H.-W., Stocker S., Zaccaria P., Bevan M., Wilson R.K., de la Bastide M., Habermann K., Parnell L., Dedhia N., Gnoj L., Schutz K., Huang E., Spiegel L., Sekhon M., Murray J., Sheet P., Cordes M., Abu-Threideh J., Stoneking T., Kalicki J., Graves T., Harmon G., Edwards J., Latreille P., Courtney L., Cloud J., Abbott A., Scott K., Johnson D., Minx P., Bentley D., Fulton B., Miller N., Greco T., Kemp K., Kramer J., Fulton L., Mardis E., Dante M., Pepin K., Hillier L.W., Nelson J., Spieth J., Ryan E., Andrews S., Geisel C., Layman D., Du H., Ali J., Berghoff A., Jones K., Drone K., Cotton M., Joshu C., Antonoiu B., Zidanic M., Strong C., Sun H., Lamar B., Yordan C., Ma P., Zhong J., Preston R., Vil D., Shekher M., Matero A., Shah R., Swaby I.K., O'Shaughnessy A., Rodriguez M., Hoffman J., Till S., Granat S., Shohdy N., Hasegawa A., Hameed A., Lodhi M., Johnson A., Chen E., Marra M.A., Martienssen R., McCombie W.R.
    Nature 402:769-777(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: cv. Columbia.
  4. The Arabidopsis Information Resource (TAIR)
    Submitted (APR-2011) to the EMBL/GenBank/DDBJ databases
    Cited for: GENOME REANNOTATION.
    Strain: cv. Columbia.
  5. "Empirical analysis of transcriptional activity in the Arabidopsis genome."
    Yamada K., Lim J., Dale J.M., Chen H., Shinn P., Palm C.J., Southwick A.M., Wu H.C., Kim C.J., Nguyen M., Pham P.K., Cheuk R.F., Karlin-Newmann G., Liu S.X., Lam B., Sakano H., Wu T., Yu G.
    , Miranda M., Quach H.L., Tripp M., Chang C.H., Lee J.M., Toriumi M.J., Chan M.M., Tang C.C., Onodera C.S., Deng J.M., Akiyama K., Ansari Y., Arakawa T., Banh J., Banno F., Bowser L., Brooks S.Y., Carninci P., Chao Q., Choy N., Enju A., Goldsmith A.D., Gurjal M., Hansen N.F., Hayashizaki Y., Johnson-Hopson C., Hsuan V.W., Iida K., Karnes M., Khan S., Koesema E., Ishida J., Jiang P.X., Jones T., Kawai J., Kamiya A., Meyers C., Nakajima M., Narusaka M., Seki M., Sakurai T., Satou M., Tamse R., Vaysberg M., Wallender E.K., Wong C., Yamamura Y., Yuan S., Shinozaki K., Davis R.W., Theologis A., Ecker J.R.
    Science 302:842-846(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Strain: cv. Columbia.
  6. "Whole genome sequence comparisons and 'full-length' cDNA sequences: a combined approach to evaluate and improve Arabidopsis genome annotation."
    Castelli V., Aury J.-M., Jaillon O., Wincker P., Clepet C., Menard M., Cruaud C., Quetier F., Scarpelli C., Schaechter V., Temple G., Caboche M., Weissenbach J., Salanoubat M.
    Genome Res. 14:406-413(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 2 AND 3).
    Strain: cv. Columbia.
  7. "PROPORZ1, a putative Arabidopsis transcriptional adaptor protein, mediates auxin and cytokinin signals in the control of cell proliferation."
    Sieberer T., Hauser M.-T., Seifert G.J., Luschnig C.
    Curr. Biol. 13:837-842(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, DISRUPTION PHENOTYPE, TISSUE SPECIFICITY, SUBCELLULAR LOCATION, IDENTIFICATION.
  8. "Disruption mutations of ADA2b and GCN5 transcriptional adaptor genes dramatically affect Arabidopsis growth, development, and gene expression."
    Vlachonasios K.E., Thomashow M.F., Triezenberg S.J.
    Plant Cell 15:626-638(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, DISRUPTION PHENOTYPE.
  9. "Physical and functional interactions of Arabidopsis ADA2 transcriptional coactivator proteins with the acetyltransferase GCN5 and with the cold-induced transcription factor CBF1."
    Mao Y., Pavangadkar K.A., Thomashow M.F., Triezenberg S.J.
    Biochim. Biophys. Acta 1759:69-79(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: INTERACTION WITH GCN5 AND DREB1B/CBF1, ACETYLATION AT LYS-216, IDENTIFICATION BY MASS SPECTROMETRY, MUTAGENESIS OF LYS-216.

Entry informationi

Entry nameiTAD2B_ARATH
AccessioniPrimary (citable) accession number: Q9ATB4
Secondary accession number(s): O23486, Q3EA06, Q3EA07
Entry historyi
Integrated into UniProtKB/Swiss-Prot: January 9, 2007
Last sequence update: June 1, 2001
Last modified: June 8, 2016
This is version 123 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. Arabidopsis thaliana
    Arabidopsis thaliana: entries and gene names
  2. 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.