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Protein

Kelch-like protein 7

Gene

KLHL7

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

Functioni

Substrate-specific adapter of a BCR (BTB-CUL3-RBX1) E3 ubiquitin ligase complex. The BCR(KLHL7) complex acts by mediating ubiquitination and subsequent degradation of substrate proteins. Probably mediates 'Lys-48'-linked ubiquitination.1 Publication

Pathwayi: protein ubiquitination

This protein is involved in the pathway protein ubiquitination, which is part of Protein modification.
View all proteins of this organism that are known to be involved in the pathway protein ubiquitination and in Protein modification.

GO - Molecular functioni

  • identical protein binding Source: IntAct
  • protein homodimerization activity Source: UniProtKB

GO - Biological processi

Complete GO annotation...

Keywords - Biological processi

Ubl conjugation pathway

Enzyme and pathway databases

UniPathwayiUPA00143.

Names & Taxonomyi

Protein namesi
Recommended name:
Kelch-like protein 7
Gene namesi
Name:KLHL7
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 7

Organism-specific databases

HGNCiHGNC:15646. KLHL7.

Subcellular locationi

GO - Cellular componenti

  • Cul3-RING ubiquitin ligase complex Source: UniProtKB
  • cytoplasm Source: HPA
  • nucleolus Source: LIFEdb
  • nucleoplasm Source: HPA
  • nucleus Source: HPA
  • plasma membrane Source: HPA
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Involvement in diseasei

Retinitis pigmentosa 42 (RP42)3 Publications
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well.
See also OMIM:612943
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_060672150S → N in RP42. 2 PublicationsCorresponds to variant rs137853112dbSNPEnsembl.1
Natural variantiVAR_060673153A → T in RP42; impairs interaction with CUL3 and ubiquitin ligase activity of the BCR(KLHL7) complex. 3 PublicationsCorresponds to variant rs137853114dbSNPEnsembl.1
Natural variantiVAR_060674153A → V in RP42; impairs interaction with CUL3 and ubiquitin ligase activity of the BCR(KLHL7) complex. 4 PublicationsCorresponds to variant rs137853113dbSNPEnsembl.1

Keywords - Diseasei

Disease mutation, Retinitis pigmentosa

Organism-specific databases

DisGeNETi55975.
MalaCardsiKLHL7.
MIMi612943. phenotype.
OpenTargetsiENSG00000122550.
Orphaneti791. Retinitis pigmentosa.
PharmGKBiPA38392.

Polymorphism and mutation databases

BioMutaiKLHL7.
DMDMi116242609.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00002289881 – 586Kelch-like protein 7Add BLAST586

Proteomic databases

EPDiQ8IXQ5.
MaxQBiQ8IXQ5.
PaxDbiQ8IXQ5.
PeptideAtlasiQ8IXQ5.
PRIDEiQ8IXQ5.

PTM databases

iPTMnetiQ8IXQ5.
PhosphoSitePlusiQ8IXQ5.

Expressioni

Tissue specificityi

Widely expressed, with highest levels in adult and fetal heart, CNS and adult testis.1 Publication

Gene expression databases

BgeeiENSG00000122550.
CleanExiHS_KLHL7.
ExpressionAtlasiQ8IXQ5. baseline and differential.
GenevisibleiQ8IXQ5. HS.

Organism-specific databases

HPAiHPA029491.
HPA029492.

Interactioni

Subunit structurei

Homodimer. Component of the BCR(KLHL7) E3 ubiquitin ligase complex, at least composed of CUL3 and KLHL7 and RBX1.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
itself7EBI-6153160,EBI-6153160
CUL3Q136187EBI-6153160,EBI-456129

GO - Molecular functioni

  • identical protein binding Source: IntAct
  • protein homodimerization activity Source: UniProtKB

Protein-protein interaction databases

BioGridi121021. 28 interactors.
IntActiQ8IXQ5. 18 interactors.
MINTiMINT-4718705.
STRINGi9606.ENSP00000343273.

Structurei

Secondary structure

1586
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi293 – 298Combined sources6
Beta strandi305 – 309Combined sources5
Turni311 – 313Combined sources3
Beta strandi316 – 318Combined sources3
Beta strandi330 – 334Combined sources5
Beta strandi337 – 341Combined sources5
Beta strandi344 – 348Combined sources5
Beta strandi351 – 356Combined sources6
Turni357 – 360Combined sources4
Beta strandi361 – 366Combined sources6
Beta strandi376 – 380Combined sources5
Beta strandi383 – 387Combined sources5
Beta strandi400 – 404Combined sources5
Turni405 – 408Combined sources4
Beta strandi409 – 413Combined sources5
Beta strandi424 – 428Combined sources5
Beta strandi431 – 435Combined sources5
Beta strandi438 – 440Combined sources3
Turni442 – 444Combined sources3
Beta strandi451 – 455Combined sources5
Turni456 – 459Combined sources4
Beta strandi460 – 464Combined sources5
Beta strandi475 – 479Combined sources5
Beta strandi482 – 486Combined sources5
Beta strandi493 – 495Combined sources3
Beta strandi498 – 502Combined sources5
Turni503 – 506Combined sources4
Beta strandi507 – 510Combined sources4
Beta strandi522 – 526Combined sources5
Beta strandi529 – 534Combined sources6
Beta strandi538 – 541Combined sources4
Beta strandi544 – 549Combined sources6
Turni550 – 553Combined sources4
Beta strandi554 – 562Combined sources9
Beta strandi570 – 575Combined sources6

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3II7X-ray1.63A283-586[»]
ProteinModelPortaliQ8IXQ5.
SMRiQ8IXQ5.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ8IXQ5.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini44 – 111BTBPROSITE-ProRule annotationAdd BLAST68
Domaini146 – 248BACKAdd BLAST103
Repeati294 – 336Kelch 1Add BLAST43
Repeati337 – 382Kelch 2Add BLAST46
Repeati383 – 430Kelch 3Add BLAST48
Repeati431 – 481Kelch 4Add BLAST51
Repeati483 – 528Kelch 5Add BLAST46
Repeati530 – 575Kelch 6Add BLAST46

Sequence similaritiesi

Contains 1 BTB (POZ) domain.PROSITE-ProRule annotation
Contains 6 Kelch repeats.Curated

Keywords - Domaini

Kelch repeat, Repeat

Phylogenomic databases

eggNOGiKOG4441. Eukaryota.
ENOG410XNX8. LUCA.
GeneTreeiENSGT00760000119153.
HOGENOMiHOG000230816.
HOVERGENiHBG106113.
InParanoidiQ8IXQ5.
KOiK10445.
OMAiNNCEVYD.
OrthoDBiEOG091G03G7.
PhylomeDBiQ8IXQ5.
TreeFamiTF351653.

Family and domain databases

Gene3Di2.120.10.80. 1 hit.
InterProiIPR011705. BACK.
IPR017096. BTB-kelch_protein.
IPR000210. BTB/POZ_dom.
IPR015915. Kelch-typ_b-propeller.
IPR006652. Kelch_1.
IPR030599. KLHL7.
IPR011333. SKP1/BTB/POZ.
[Graphical view]
PANTHERiPTHR24412:SF216. PTHR24412:SF216. 1 hit.
PfamiPF07707. BACK. 1 hit.
PF00651. BTB. 1 hit.
PF01344. Kelch_1. 3 hits.
[Graphical view]
PIRSFiPIRSF037037. Kelch-like_protein_gigaxonin. 1 hit.
SMARTiSM00875. BACK. 1 hit.
SM00225. BTB. 1 hit.
SM00612. Kelch. 4 hits.
[Graphical view]
SUPFAMiSSF54695. SSF54695. 1 hit.
PROSITEiPS50097. BTB. 1 hit.
[Graphical view]

Sequences (5)i

Sequence statusi: Complete.

This entry describes 5 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q8IXQ5-1) [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
MAASGVEKSS KKKTEKKLAA REEAKLLAGF MGVMNNMRKQ KTLCDVILMV
60 70 80 90 100
QERKIPAHRV VLAAASHFFN LMFTTNMLES KSFEVELKDA EPDIIEQLVE
110 120 130 140 150
FAYTARISVN SNNVQSLLDA ANQYQIEPVK KMCVDFLKEQ VDASNCLGIS
160 170 180 190 200
VLAECLDCPE LKATADDFIH QHFTEVYKTD EFLQLDVKRV THLLNQDTLT
210 220 230 240 250
VRAEDQVYDA AVRWLKYDEP NRQPFMVDIL AKVRFPLISK NFLSKTVQAE
260 270 280 290 300
PLIQDNPECL KMVISGMRYH LLSPEDREEL VDGTRPRRKK HDYRIALFGG
310 320 330 340 350
SQPQSCRYFN PKDYSWTDIR CPFEKRRDAA CVFWDNVVYI LGGSQLFPIK
360 370 380 390 400
RMDCYNVVKD SWYSKLGPPT PRDSLAACAA EGKIYTSGGS EVGNSALYLF
410 420 430 440 450
ECYDTRTESW HTKPSMLTQR CSHGMVEANG LIYVCGGSLG NNVSGRVLNS
460 470 480 490 500
CEVYDPATET WTELCPMIEA RKNHGLVFVK DKIFAVGGQN GLGGLDNVEY
510 520 530 540 550
YDIKLNEWKM VSPMPWKGVT VKCAAVGSIV YVLAGFQGVG RLGHILEYNT
560 570 580
ETDKWVANSK VRAFPVTSCL ICVVDTCGAN EETLET
Length:586
Mass (Da):65,992
Last modified:October 17, 2006 - v2
Checksum:iFA4ED8F1567AC7A8
GO
Isoform 2 (identifier: Q8IXQ5-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-40: MAASGVEKSSKKKTEKKLAAREEAKLLAGFMGVMNNMRKQ → MLGGTDCRTFLTSHINLK

Show »
Length:564
Mass (Da):63,601
Checksum:iD5FFE152DEA3D63E
GO
Isoform 3 (identifier: Q8IXQ5-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     149-166: ISVLAECLDCPELKATAD → EAEKVDQSLPECGMLFTV
     167-586: Missing.

Show »
Length:166
Mass (Da):18,568
Checksum:iD48BE4F0B94F1386
GO
Isoform 4 (identifier: Q8IXQ5-4) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-40: MAASGVEKSSKKKTEKKLAAREEAKLLAGFMGVMNNMRKQ → MLGGTDCRTFLTSHINLK
     149-166: ISVLAECLDCPELKATAD → EAEKVDQSLPECGMLFTV
     167-586: Missing.

Show »
Length:144
Mass (Da):16,177
Checksum:i90CD7ACD869455D7
GO
Isoform 5 (identifier: Q8IXQ5-5) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-48: Missing.

Show »
Length:538
Mass (Da):60,725
Checksum:i8B7ABA54C28D56C1
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti85V → L in AAH39585 (PubMed:15489334).Curated1
Sequence conflicti138K → R in BAB71175 (PubMed:14702039).Curated1
Sequence conflicti507E → D in BAH12925 (PubMed:14702039).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_060672150S → N in RP42. 2 PublicationsCorresponds to variant rs137853112dbSNPEnsembl.1
Natural variantiVAR_060673153A → T in RP42; impairs interaction with CUL3 and ubiquitin ligase activity of the BCR(KLHL7) complex. 3 PublicationsCorresponds to variant rs137853114dbSNPEnsembl.1
Natural variantiVAR_060674153A → V in RP42; impairs interaction with CUL3 and ubiquitin ligase activity of the BCR(KLHL7) complex. 4 PublicationsCorresponds to variant rs137853113dbSNPEnsembl.1
Natural variantiVAR_060675255D → N in a patient with retinitis pigmentosa; uncertain pathological significance. 1 Publication1
Natural variantiVAR_060676423H → Y.1 Publication1
Natural variantiVAR_060677472K → Q in a patient with retinitis pigmentosa; uncertain pathological significance. 1 Publication1
Isoform 2 (identifier: Q8IXQ5-2)
Natural varianti18K → R.Corresponds to variant rs17147682dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0469741 – 48Missing in isoform 5. 1 PublicationAdd BLAST48
Alternative sequenceiVSP_0384161 – 40MAASG…NMRKQ → MLGGTDCRTFLTSHINLK in isoform 2 and isoform 4. 3 PublicationsAdd BLAST40
Alternative sequenceiVSP_038417149 – 166ISVLA…KATAD → EAEKVDQSLPECGMLFTV in isoform 3 and isoform 4. 2 PublicationsAdd BLAST18
Alternative sequenceiVSP_038418167 – 586Missing in isoform 3 and isoform 4. 2 PublicationsAdd BLAST420

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF111113 mRNA. Translation: AAF27196.1.
AL136597 mRNA. Translation: CAB66532.1.
AK056390 mRNA. Translation: BAB71175.1.
AK299006 mRNA. Translation: BAH12925.1.
EF560731 mRNA. Translation: ABQ59041.1.
AC005082 Genomic DNA. No translation available.
AC006039 Genomic DNA. Translation: AAO21916.1.
AC073992 Genomic DNA. No translation available.
CH236948 Genomic DNA. Translation: EAL24261.1.
CH471073 Genomic DNA. Translation: EAW93770.1.
CH471073 Genomic DNA. Translation: EAW93773.1.
CH471073 Genomic DNA. Translation: EAW93774.1.
BC009555 mRNA. Translation: AAH09555.1.
BC039585 mRNA. Translation: AAH39585.1.
CCDSiCCDS34609.1. [Q8IXQ5-1]
CCDS5378.2. [Q8IXQ5-5]
CCDS55095.1. [Q8IXQ5-3]
RefSeqiNP_001026880.2. NM_001031710.2. [Q8IXQ5-1]
NP_001165899.1. NM_001172428.1. [Q8IXQ5-3]
NP_061334.4. NM_018846.4. [Q8IXQ5-5]
XP_016867928.1. XM_017012439.1. [Q8IXQ5-2]
UniGeneiHs.654817.

Genome annotation databases

EnsembliENST00000322275; ENSP00000323270; ENSG00000122550. [Q8IXQ5-3]
ENST00000339077; ENSP00000343273; ENSG00000122550. [Q8IXQ5-1]
ENST00000409689; ENSP00000386263; ENSG00000122550. [Q8IXQ5-5]
ENST00000410047; ENSP00000386999; ENSG00000122550. [Q8IXQ5-4]
GeneIDi55975.
KEGGihsa:55975.
UCSCiuc003svq.4. human. [Q8IXQ5-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF111113 mRNA. Translation: AAF27196.1.
AL136597 mRNA. Translation: CAB66532.1.
AK056390 mRNA. Translation: BAB71175.1.
AK299006 mRNA. Translation: BAH12925.1.
EF560731 mRNA. Translation: ABQ59041.1.
AC005082 Genomic DNA. No translation available.
AC006039 Genomic DNA. Translation: AAO21916.1.
AC073992 Genomic DNA. No translation available.
CH236948 Genomic DNA. Translation: EAL24261.1.
CH471073 Genomic DNA. Translation: EAW93770.1.
CH471073 Genomic DNA. Translation: EAW93773.1.
CH471073 Genomic DNA. Translation: EAW93774.1.
BC009555 mRNA. Translation: AAH09555.1.
BC039585 mRNA. Translation: AAH39585.1.
CCDSiCCDS34609.1. [Q8IXQ5-1]
CCDS5378.2. [Q8IXQ5-5]
CCDS55095.1. [Q8IXQ5-3]
RefSeqiNP_001026880.2. NM_001031710.2. [Q8IXQ5-1]
NP_001165899.1. NM_001172428.1. [Q8IXQ5-3]
NP_061334.4. NM_018846.4. [Q8IXQ5-5]
XP_016867928.1. XM_017012439.1. [Q8IXQ5-2]
UniGeneiHs.654817.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3II7X-ray1.63A283-586[»]
ProteinModelPortaliQ8IXQ5.
SMRiQ8IXQ5.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi121021. 28 interactors.
IntActiQ8IXQ5. 18 interactors.
MINTiMINT-4718705.
STRINGi9606.ENSP00000343273.

PTM databases

iPTMnetiQ8IXQ5.
PhosphoSitePlusiQ8IXQ5.

Polymorphism and mutation databases

BioMutaiKLHL7.
DMDMi116242609.

Proteomic databases

EPDiQ8IXQ5.
MaxQBiQ8IXQ5.
PaxDbiQ8IXQ5.
PeptideAtlasiQ8IXQ5.
PRIDEiQ8IXQ5.

Protocols and materials databases

DNASUi55975.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000322275; ENSP00000323270; ENSG00000122550. [Q8IXQ5-3]
ENST00000339077; ENSP00000343273; ENSG00000122550. [Q8IXQ5-1]
ENST00000409689; ENSP00000386263; ENSG00000122550. [Q8IXQ5-5]
ENST00000410047; ENSP00000386999; ENSG00000122550. [Q8IXQ5-4]
GeneIDi55975.
KEGGihsa:55975.
UCSCiuc003svq.4. human. [Q8IXQ5-1]

Organism-specific databases

CTDi55975.
DisGeNETi55975.
GeneCardsiKLHL7.
GeneReviewsiKLHL7.
HGNCiHGNC:15646. KLHL7.
HPAiHPA029491.
HPA029492.
MalaCardsiKLHL7.
MIMi611119. gene.
612943. phenotype.
neXtProtiNX_Q8IXQ5.
OpenTargetsiENSG00000122550.
Orphaneti791. Retinitis pigmentosa.
PharmGKBiPA38392.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG4441. Eukaryota.
ENOG410XNX8. LUCA.
GeneTreeiENSGT00760000119153.
HOGENOMiHOG000230816.
HOVERGENiHBG106113.
InParanoidiQ8IXQ5.
KOiK10445.
OMAiNNCEVYD.
OrthoDBiEOG091G03G7.
PhylomeDBiQ8IXQ5.
TreeFamiTF351653.

Enzyme and pathway databases

UniPathwayiUPA00143.

Miscellaneous databases

ChiTaRSiKLHL7. human.
EvolutionaryTraceiQ8IXQ5.
GeneWikiiKLHL7.
GenomeRNAii55975.
PROiQ8IXQ5.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000122550.
CleanExiHS_KLHL7.
ExpressionAtlasiQ8IXQ5. baseline and differential.
GenevisibleiQ8IXQ5. HS.

Family and domain databases

Gene3Di2.120.10.80. 1 hit.
InterProiIPR011705. BACK.
IPR017096. BTB-kelch_protein.
IPR000210. BTB/POZ_dom.
IPR015915. Kelch-typ_b-propeller.
IPR006652. Kelch_1.
IPR030599. KLHL7.
IPR011333. SKP1/BTB/POZ.
[Graphical view]
PANTHERiPTHR24412:SF216. PTHR24412:SF216. 1 hit.
PfamiPF07707. BACK. 1 hit.
PF00651. BTB. 1 hit.
PF01344. Kelch_1. 3 hits.
[Graphical view]
PIRSFiPIRSF037037. Kelch-like_protein_gigaxonin. 1 hit.
SMARTiSM00875. BACK. 1 hit.
SM00225. BTB. 1 hit.
SM00612. Kelch. 4 hits.
[Graphical view]
SUPFAMiSSF54695. SSF54695. 1 hit.
PROSITEiPS50097. BTB. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiKLHL7_HUMAN
AccessioniPrimary (citable) accession number: Q8IXQ5
Secondary accession number(s): A4D144
, B7Z5I9, G5E9G3, Q7Z765, Q96MV2, Q9BQF8, Q9UDQ9
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 21, 2006
Last sequence update: October 17, 2006
Last modified: November 2, 2016
This is version 130 of the entry and version 2 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 7
    Human chromosome 7: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  6. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  7. 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.