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Protein

60S ribosomal protein L7

Gene

RPL7

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

Functioni

Binds to G-rich structures in 28S rRNA and in mRNAs. Plays a regulatory role in the translation apparatus; inhibits cell-free translation of mRNAs.

GO - Molecular functioni

  1. DNA binding Source: MGI
  2. mRNA binding Source: MGI
  3. poly(A) RNA binding Source: UniProtKB
  4. protein homodimerization activity Source: MGI
  5. RNA binding Source: ProtInc
  6. structural constituent of ribosome Source: UniProtKB

GO - Biological processi

  1. cellular protein metabolic process Source: Reactome
  2. gene expression Source: Reactome
  3. nuclear-transcribed mRNA catabolic process, nonsense-mediated decay Source: Reactome
  4. ribosomal large subunit biogenesis Source: UniProtKB
  5. rRNA processing Source: UniProtKB
  6. SRP-dependent cotranslational protein targeting to membrane Source: Reactome
  7. translation Source: UniProtKB
  8. translational elongation Source: Reactome
  9. translational initiation Source: Reactome
  10. translational termination Source: Reactome
  11. viral life cycle Source: Reactome
  12. viral process Source: Reactome
  13. viral transcription Source: Reactome
Complete GO annotation...

Keywords - Molecular functioni

Ribonucleoprotein, Ribosomal protein

Keywords - Ligandi

RNA-binding

Enzyme and pathway databases

ReactomeiREACT_115902. SRP-dependent cotranslational protein targeting to membrane.
REACT_1404. Peptide chain elongation.
REACT_1797. Formation of a pool of free 40S subunits.
REACT_1986. Eukaryotic Translation Termination.
REACT_2085. GTP hydrolysis and joining of the 60S ribosomal subunit.
REACT_75768. Nonsense Mediated Decay (NMD) independent of the Exon Junction Complex (EJC).
REACT_75822. Nonsense Mediated Decay (NMD) enhanced by the Exon Junction Complex (EJC).
REACT_79. L13a-mediated translational silencing of Ceruloplasmin expression.
REACT_9491. Viral mRNA Translation.

Names & Taxonomyi

Protein namesi
Recommended name:
60S ribosomal protein L7
Gene namesi
Name:RPL7
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 8

Organism-specific databases

HGNCiHGNC:10363. RPL7.

Subcellular locationi

GO - Cellular componenti

  1. cytoplasm Source: UniProtKB
  2. cytosol Source: Reactome
  3. cytosolic large ribosomal subunit Source: UniProtKB
  4. extracellular vesicular exosome Source: UniProtKB
  5. focal adhesion Source: UniProtKB
  6. membrane Source: UniProtKB
  7. nucleolus Source: UniProtKB
  8. nucleus Source: UniProtKB
  9. ribonucleoprotein complex Source: MGI
Complete GO annotation...

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA34759.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 24824860S ribosomal protein L7PRO_0000104633Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei1 – 11N-acetylmethionine4 Publications
Modified residuei124 – 1241N6-acetyllysine1 Publication
Modified residuei127 – 1271N6-succinyllysineBy similarity
Modified residuei139 – 1391Phosphotyrosine1 Publication

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiP18124.
PaxDbiP18124.
PRIDEiP18124.

2D gel databases

SWISS-2DPAGEP18124.

PTM databases

PhosphoSiteiP18124.

Expressioni

Gene expression databases

BgeeiP18124.
CleanExiHS_RPL7.
ExpressionAtlasiP18124. baseline and differential.
GenevestigatoriP18124.

Organism-specific databases

HPAiHPA058373.

Interactioni

Subunit structurei

Homodimer.

Binary interactionsi

WithEntry#Exp.IntActNotes
IPO5O004104EBI-350806,EBI-356424
NEDD8Q158432EBI-350806,EBI-716247

Protein-protein interaction databases

BioGridi112049. 142 interactions.
IntActiP18124. 30 interactions.
MINTiMINT-1152474.
STRINGi9606.ENSP00000339795.

Structurei

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4V6Xelectron microscopy5.00CF1-248[»]
ProteinModelPortaliP18124.
SMRiP18124. Positions 24-248.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Repeati7 – 18121Add
BLAST
Repeati19 – 30122Add
BLAST
Repeati31 – 42123Add
BLAST
Repeati43 – 54124Add
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni7 – 54484 X 12 AA tandem repeatsAdd
BLAST

Sequence similaritiesi

Belongs to the ribosomal protein L30P family.Curated

Keywords - Domaini

Repeat

Phylogenomic databases

eggNOGiCOG1841.
GeneTreeiENSGT00390000006213.
HOGENOMiHOG000170917.
HOVERGENiHBG003280.
InParanoidiP18124.
KOiK02937.
OMAiPYITYGE.
OrthoDBiEOG7K9K3X.
PhylomeDBiP18124.
TreeFamiTF300740.

Family and domain databases

Gene3Di3.30.1390.20. 2 hits.
InterProiIPR018038. Ribosomal_L30_CS.
IPR016082. Ribosomal_L30_ferredoxin-like.
IPR012988. Ribosomal_L30_N.
IPR005998. Ribosomal_L7_euk.
[Graphical view]
PfamiPF00327. Ribosomal_L30. 1 hit.
PF08079. Ribosomal_L30_N. 1 hit.
[Graphical view]
SUPFAMiSSF55129. SSF55129. 1 hit.
TIGRFAMsiTIGR01310. L7. 1 hit.
PROSITEiPS00634. RIBOSOMAL_L30. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P18124-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MEGVEEKKKE VPAVPETLKK KRRNFAELKI KRLRKKFAQK MLRKARRKLI
60 70 80 90 100
YEKAKHYHKE YRQMYRTEIR MARMARKAGN FYVPAEPKLA FVIRIRGING
110 120 130 140 150
VSPKVRKVLQ LLRLRQIFNG TFVKLNKASI NMLRIVEPYI AWGYPNLKSV
160 170 180 190 200
NELIYKRGYG KINKKRIALT DNALIARSLG KYGIICMEDL IHEIYTVGKR
210 220 230 240
FKEANNFLWP FKLSSPRGGM KKKTTHFVEG GDAGNREDQI NRLIRRMN
Length:248
Mass (Da):29,226
Last modified:November 1, 1990 - v1
Checksum:i070EB4C904E6795A
GO

Sequence cautioni

The sequence CAA41026.1 differs from that shown. Reason: Erroneous initiation. Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti48 – 481K → E in CAG33054 (Ref. 4) Curated
Sequence conflicti157 – 1571R → L in CAA41026 (PubMed:8441630).Curated
Sequence conflicti157 – 1571R → L in CAA41027 (PubMed:8441630).Curated
Sequence conflicti160 – 1601G → A in CAA41026 (PubMed:8441630).Curated
Sequence conflicti166 – 1661R → Q in CAA41026 (PubMed:8441630).Curated
Sequence conflicti173 – 1731A → S in AAA03081 (PubMed:8360149).Curated
Sequence conflicti192 – 1921H → R in CAG33054 (Ref. 4) Curated

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X57958 mRNA. Translation: CAA41026.1. Different initiation.
X57959 mRNA. Translation: CAA41027.1.
L16558 mRNA. Translation: AAA03081.1.
X52967 mRNA. Translation: CAA37139.1.
CR456773 mRNA. Translation: CAG33054.1.
AK291119 mRNA. Translation: BAF83808.1.
AK313365 mRNA. Translation: BAG36165.1.
BC006095 mRNA. Translation: AAH06095.1.
BC008850 mRNA. Translation: AAH08850.1.
BC009599 mRNA. Translation: AAH09599.1.
BC071671 mRNA. Translation: AAH71671.1.
BC071894 mRNA. Translation: AAH71894.1.
BC071895 mRNA. Translation: AAH71895.1.
BC087837 mRNA. Translation: AAH87837.1.
CCDSiCCDS6212.1.
PIRiS11709. R5HU7.
RefSeqiNP_000962.2. NM_000971.3.
UniGeneiHs.421257.
Hs.571841.

Genome annotation databases

EnsembliENST00000352983; ENSP00000339795; ENSG00000147604.
GeneIDi6129.
KEGGihsa:6129.
UCSCiuc003xzg.3. human.

Polymorphism databases

DMDMi133021.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X57958 mRNA. Translation: CAA41026.1. Different initiation.
X57959 mRNA. Translation: CAA41027.1.
L16558 mRNA. Translation: AAA03081.1.
X52967 mRNA. Translation: CAA37139.1.
CR456773 mRNA. Translation: CAG33054.1.
AK291119 mRNA. Translation: BAF83808.1.
AK313365 mRNA. Translation: BAG36165.1.
BC006095 mRNA. Translation: AAH06095.1.
BC008850 mRNA. Translation: AAH08850.1.
BC009599 mRNA. Translation: AAH09599.1.
BC071671 mRNA. Translation: AAH71671.1.
BC071894 mRNA. Translation: AAH71894.1.
BC071895 mRNA. Translation: AAH71895.1.
BC087837 mRNA. Translation: AAH87837.1.
CCDSiCCDS6212.1.
PIRiS11709. R5HU7.
RefSeqiNP_000962.2. NM_000971.3.
UniGeneiHs.421257.
Hs.571841.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4V6Xelectron microscopy5.00CF1-248[»]
ProteinModelPortaliP18124.
SMRiP18124. Positions 24-248.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi112049. 142 interactions.
IntActiP18124. 30 interactions.
MINTiMINT-1152474.
STRINGi9606.ENSP00000339795.

PTM databases

PhosphoSiteiP18124.

Polymorphism databases

DMDMi133021.

2D gel databases

SWISS-2DPAGEP18124.

Proteomic databases

MaxQBiP18124.
PaxDbiP18124.
PRIDEiP18124.

Protocols and materials databases

DNASUi6129.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000352983; ENSP00000339795; ENSG00000147604.
GeneIDi6129.
KEGGihsa:6129.
UCSCiuc003xzg.3. human.

Organism-specific databases

CTDi6129.
GeneCardsiGC08M074202.
H-InvDBHIX0058339.
HGNCiHGNC:10363. RPL7.
HPAiHPA058373.
MIMi604166. gene.
neXtProtiNX_P18124.
PharmGKBiPA34759.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG1841.
GeneTreeiENSGT00390000006213.
HOGENOMiHOG000170917.
HOVERGENiHBG003280.
InParanoidiP18124.
KOiK02937.
OMAiPYITYGE.
OrthoDBiEOG7K9K3X.
PhylomeDBiP18124.
TreeFamiTF300740.

Enzyme and pathway databases

ReactomeiREACT_115902. SRP-dependent cotranslational protein targeting to membrane.
REACT_1404. Peptide chain elongation.
REACT_1797. Formation of a pool of free 40S subunits.
REACT_1986. Eukaryotic Translation Termination.
REACT_2085. GTP hydrolysis and joining of the 60S ribosomal subunit.
REACT_75768. Nonsense Mediated Decay (NMD) independent of the Exon Junction Complex (EJC).
REACT_75822. Nonsense Mediated Decay (NMD) enhanced by the Exon Junction Complex (EJC).
REACT_79. L13a-mediated translational silencing of Ceruloplasmin expression.
REACT_9491. Viral mRNA Translation.

Miscellaneous databases

ChiTaRSiRPL7. human.
GeneWikiiRPL7.
GenomeRNAii6129.
NextBioi23805.
PROiP18124.
SOURCEiSearch...

Gene expression databases

BgeeiP18124.
CleanExiHS_RPL7.
ExpressionAtlasiP18124. baseline and differential.
GenevestigatoriP18124.

Family and domain databases

Gene3Di3.30.1390.20. 2 hits.
InterProiIPR018038. Ribosomal_L30_CS.
IPR016082. Ribosomal_L30_ferredoxin-like.
IPR012988. Ribosomal_L30_N.
IPR005998. Ribosomal_L7_euk.
[Graphical view]
PfamiPF00327. Ribosomal_L30. 1 hit.
PF08079. Ribosomal_L30_N. 1 hit.
[Graphical view]
SUPFAMiSSF55129. SSF55129. 1 hit.
TIGRFAMsiTIGR01310. L7. 1 hit.
PROSITEiPS00634. RIBOSOMAL_L30. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Structural and functional properties of ribosomal protein L7 from humans and rodents."
    Hemmerich P., von Mikecz A., Neumann F., Soezen O., Wolff-Vorbeck G., Zoebelein R., Krawinkel U.
    Nucleic Acids Res. 21:223-231(1992) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], CHARACTERIZATION.
  2. "Identification of a transcript that is down-regulated in senescent human fibroblasts. Cloning, sequence analysis, and regulation of the human L7 ribosomal protein gene."
    Seshadri T., Uzman J.A., Oshima J., Campisi J.
    J. Biol. Chem. 268:18474-18480(1992) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
    Tissue: Fibroblast.
  3. Schneider R., Herzog H., Hfferer L., Schweiger M.
    Submitted (APR-1990) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  4. "Cloning of human full open reading frames in Gateway(TM) system entry vector (pDONR201)."
    Ebert L., Schick M., Neubert P., Schatten R., Henze S., Korn B.
    Submitted (MAY-2004) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
  5. "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(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Tissue: Thymus.
  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(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Tissue: Bone marrow, Eye, Lung, Mammary gland, Muscle and Skin.
  7. Bienvenut W.V., Boldt K., von Kriegsheim A.F., Kolch W.
    Submitted (JUN-2007) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 1-7; 10-20; 48-53; 77-88; 107-113; 128-156; 167-177; 201-212 AND 224-242, ACETYLATION AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY.
    Tissue: Hepatoma.
  8. "Human ribosomal protein L7 inhibits cell-free translation in reticulocyte lysates and affects the expression of nuclear proteins upon stable transfection into Jurkat T-lymphoma cells."
    Neumann F., Hemmerich P., von Mikecz A., Peter H.-H., Krawinkel U.
    Nucleic Acids Res. 23:195-202(1994) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION.
  9. "Characterization and analysis of posttranslational modifications of the human large cytoplasmic ribosomal subunit proteins by mass spectrometry and Edman sequencing."
    Odintsova T.I., Muller E.C., Ivanov A.V., Egorov T.A., Bienert R., Vladimirov S.N., Kostka S., Otto A., Wittmann-Liebold B., Karpova G.G.
    J. Protein Chem. 22:249-258(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY.
  10. "Immunoaffinity profiling of tyrosine phosphorylation in cancer cells."
    Rush J., Moritz A., Lee K.A., Guo A., Goss V.L., Spek E.J., Zhang H., Zha X.-M., Polakiewicz R.D., Comb M.J.
    Nat. Biotechnol. 23:94-101(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT TYR-139, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  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(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  12. "Lysine acetylation targets protein complexes and co-regulates major cellular functions."
    Choudhary C., Kumar C., Gnad F., Nielsen M.L., Rehman M., Walther T.C., Olsen J.V., Mann M.
    Science 325:834-840(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT LYS-124, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  13. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  14. Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT MET-1, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  15. "An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
    Bian Y., Song C., Cheng K., Dong M., Wang F., Huang J., Sun D., Wang L., Ye M., Zou H.
    J. Proteomics 96:253-262(2013) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Liver.
  16. Cited for: STRUCTURE BY ELECTRON MICROSCOPY (5.0 ANGSTROMS) OF 80S RIBOSOME.

Entry informationi

Entry nameiRL7_HUMAN
AccessioniPrimary (citable) accession number: P18124
Secondary accession number(s): A8K504
, Q15289, Q3KQU0, Q5I0X1, Q6IBM9
Entry historyi
Integrated into UniProtKB/Swiss-Prot: November 1, 1990
Last sequence update: November 1, 1990
Last modified: April 1, 2015
This is version 161 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, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 8
    Human chromosome 8: 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. Ribosomal proteins
    Ribosomal proteins families and list of entries
  5. 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.