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Protein

Ribonuclease P/MRP protein subunit POP5

Gene

POP5

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

Functioni

Component of ribonuclease P, a protein complex that generates mature tRNA molecules by cleaving their 5'-ends. Also a component of RNase MRP.1 Publication

Catalytic activityi

Endonucleolytic cleavage of RNA, removing 5'-extranucleotides from tRNA precursor.1 Publication

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Hydrolase

Keywords - Biological processi

tRNA processing

Names & Taxonomyi

Protein namesi
Recommended name:
Ribonuclease P/MRP protein subunit POP5 (EC:3.1.26.5)
Short name:
hPop5
Gene namesi
Name:POP5
ORF Names:AD-008, HSPC004, x0003
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 12

Organism-specific databases

HGNCiHGNC:17689. POP5.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA128394660.

Polymorphism and mutation databases

BioMutaiPOP5.
DMDMi74731042.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 163163Ribonuclease P/MRP protein subunit POP5PRO_0000239007Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei154 – 1541Phosphoserine4 Publications

Keywords - PTMi

Phosphoprotein

Proteomic databases

MaxQBiQ969H6.
PaxDbiQ969H6.
PRIDEiQ969H6.

PTM databases

PhosphoSiteiQ969H6.

Expressioni

Gene expression databases

BgeeiQ969H6.
CleanExiHS_POP5.
GenevisibleiQ969H6. HS.

Organism-specific databases

HPAiHPA047598.

Interactioni

Subunit structurei

Component of nuclear RNase P and RNase MRP ribonucleoproteins. RNase P consists of an RNA moiety and at least 8 protein subunits; POP1, RPP14, RPP20/POP7, RPP25, RPP29/POP4, RPP30, RPP38 and RPP40. RNase MRP consists of an RNA moiety and at least 9 protein subunits; POP1, RPP14, RPP20/POP7, RPP25, RPP29/POP4, RPP30, RPP38, RPP40, POP5 and RPP21.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
CAMK2BQ135543EBI-366525,EBI-1058722
CCDC102BA1A4H13EBI-366525,EBI-10171570
CEP44Q9C0F13EBI-366525,EBI-744115
KRT40Q6A1623EBI-366525,EBI-10171697
POP4O957072EBI-366525,EBI-366477
RELQ048643EBI-366525,EBI-307352
taxP140793EBI-366525,EBI-9675698From a different organism.
TRAF1Q130773EBI-366525,EBI-359224

Protein-protein interaction databases

BioGridi119502. 12 interactions.
IntActiQ969H6. 11 interactions.
STRINGi9606.ENSP00000350098.

Structurei

3D structure databases

ProteinModelPortaliQ969H6.
SMRiQ969H6. Positions 1-119.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Phylogenomic databases

eggNOGiNOG284693.
GeneTreeiENSGT00390000012331.
HOGENOMiHOG000293345.
HOVERGENiHBG082157.
InParanoidiQ969H6.
KOiK03537.
OMAiCEVVSDD.
OrthoDBiEOG7GTT69.
PhylomeDBiQ969H6.
TreeFamiTF317496.

Family and domain databases

InterProiIPR016819. RNase_P/MRP_POP5.
IPR002759. RNase_P/MRP_subunit.
[Graphical view]
PANTHERiPTHR13004:SF8. PTHR13004:SF8. 1 hit.
PfamiPF01900. RNase_P_Rpp14. 1 hit.
[Graphical view]
PIRSFiPIRSF023803. Ribonuclease_P_prd. 1 hit.

Sequences (2)i

Sequence statusi: Complete.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q969H6-1) [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
MVRFKHRYLL CELVSDDPRC RLSLDDRVLS SLVRDTIARV HGTFGAAACS
60 70 80 90 100
IGFAVRYLNA YTGIVLLRCR KEFYQLVWSA LPFITYLENK GHRYPCFFNT
110 120 130 140 150
LHVGGTIRTC QKFLIQYNRR QLLILLQNCT DEGEREAIQK SVTRSCLLEE
160
EEESGEEAAE AME
Length:163
Mass (Da):18,820
Last modified:December 1, 2001 - v1
Checksum:iDF436E60B3DD50C1
GO
Isoform 2 (identifier: Q969H6-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     55-104: Missing.

Note: No experimental confirmation available.
Show »
Length:113
Mass (Da):12,826
Checksum:i1004F004EBE8E949
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti47 – 482AA → P in AAF17213 (PubMed:10931946).Curated
Sequence conflicti47 – 482AA → P in AAD20966 (PubMed:11042152).Curated
Sequence conflicti99 – 991N → D in BAD96926 (Ref. 5) Curated
Sequence conflicti102 – 1021H → R in BAD96926 (Ref. 5) Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei55 – 10450Missing in isoform 2. 1 PublicationVSP_042733Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AJ306296 mRNA. Translation: CAC59822.1.
AF117232 mRNA. Translation: AAF17213.1.
AF070660 mRNA. Translation: AAD20966.1.
AK303144 mRNA. Translation: BAG64248.1.
AK223206 mRNA. Translation: BAD96926.1.
AC063943 Genomic DNA. No translation available.
CH471054 Genomic DNA. Translation: EAW98206.1.
BC012505 mRNA. Translation: AAH12505.1.
CCDSiCCDS9202.1. [Q969H6-1]
CCDS9203.1. [Q969H6-2]
RefSeqiNP_057002.2. NM_015918.3. [Q969H6-1]
NP_937845.1. NM_198202.1. [Q969H6-2]
UniGeneiHs.279913.

Genome annotation databases

EnsembliENST00000341039; ENSP00000341791; ENSG00000167272. [Q969H6-2]
ENST00000357500; ENSP00000350098; ENSG00000167272. [Q969H6-1]
GeneIDi51367.
KEGGihsa:51367.
UCSCiuc001tys.3. human. [Q969H6-1]
uc001tyt.3. human. [Q969H6-2]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AJ306296 mRNA. Translation: CAC59822.1.
AF117232 mRNA. Translation: AAF17213.1.
AF070660 mRNA. Translation: AAD20966.1.
AK303144 mRNA. Translation: BAG64248.1.
AK223206 mRNA. Translation: BAD96926.1.
AC063943 Genomic DNA. No translation available.
CH471054 Genomic DNA. Translation: EAW98206.1.
BC012505 mRNA. Translation: AAH12505.1.
CCDSiCCDS9202.1. [Q969H6-1]
CCDS9203.1. [Q969H6-2]
RefSeqiNP_057002.2. NM_015918.3. [Q969H6-1]
NP_937845.1. NM_198202.1. [Q969H6-2]
UniGeneiHs.279913.

3D structure databases

ProteinModelPortaliQ969H6.
SMRiQ969H6. Positions 1-119.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi119502. 12 interactions.
IntActiQ969H6. 11 interactions.
STRINGi9606.ENSP00000350098.

PTM databases

PhosphoSiteiQ969H6.

Polymorphism and mutation databases

BioMutaiPOP5.
DMDMi74731042.

Proteomic databases

MaxQBiQ969H6.
PaxDbiQ969H6.
PRIDEiQ969H6.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000341039; ENSP00000341791; ENSG00000167272. [Q969H6-2]
ENST00000357500; ENSP00000350098; ENSG00000167272. [Q969H6-1]
GeneIDi51367.
KEGGihsa:51367.
UCSCiuc001tys.3. human. [Q969H6-1]
uc001tyt.3. human. [Q969H6-2]

Organism-specific databases

CTDi51367.
GeneCardsiGC12M121016.
HGNCiHGNC:17689. POP5.
HPAiHPA047598.
MIMi609992. gene.
neXtProtiNX_Q969H6.
PharmGKBiPA128394660.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG284693.
GeneTreeiENSGT00390000012331.
HOGENOMiHOG000293345.
HOVERGENiHBG082157.
InParanoidiQ969H6.
KOiK03537.
OMAiCEVVSDD.
OrthoDBiEOG7GTT69.
PhylomeDBiQ969H6.
TreeFamiTF317496.

Miscellaneous databases

ChiTaRSiPOP5. human.
GeneWikiiPOP5.
GenomeRNAii51367.
NextBioi54841.
PROiQ969H6.
SOURCEiSearch...

Gene expression databases

BgeeiQ969H6.
CleanExiHS_POP5.
GenevisibleiQ969H6. HS.

Family and domain databases

InterProiIPR016819. RNase_P/MRP_POP5.
IPR002759. RNase_P/MRP_subunit.
[Graphical view]
PANTHERiPTHR13004:SF8. PTHR13004:SF8. 1 hit.
PfamiPF01900. RNase_P_Rpp14. 1 hit.
[Graphical view]
PIRSFiPIRSF023803. Ribonuclease_P_prd. 1 hit.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "hPop5, a protein subunit of the human RNase MRP and RNase P endoribonucleases."
    van Eenennaam H., Lugtenberg D., Vogelzangs J.H.P., van Venrooij W.J., Pruijn G.J.M.
    J. Biol. Chem. 276:31635-31641(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), FUNCTION, CATALYTIC ACTIVITY, SUBUNIT.
  2. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Adrenal gland.
  3. "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 1).
    Tissue: Umbilical cord blood.
  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 2).
    Tissue: Thymus.
  5. Suzuki Y., Sugano S., Totoki Y., Toyoda A., Takeda T., Sakaki Y., Tanaka A., Yokoyama S.
    Submitted (APR-2005) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Kidney proximal tubule.
  6. "The finished DNA sequence of human chromosome 12."
    Scherer S.E., Muzny D.M., Buhay C.J., Chen R., Cree A., Ding Y., Dugan-Rocha S., Gill R., Gunaratne P., Harris R.A., Hawes A.C., Hernandez J., Hodgson A.V., Hume J., Jackson A., Khan Z.M., Kovar-Smith C., Lewis L.R.
    , Lozado R.J., Metzker M.L., Milosavljevic A., Miner G.R., Montgomery K.T., Morgan M.B., Nazareth L.V., Scott G., Sodergren E., Song X.-Z., Steffen D., Lovering R.C., Wheeler D.A., Worley K.C., Yuan Y., Zhang Z., Adams C.Q., Ansari-Lari M.A., Ayele M., Brown M.J., Chen G., Chen Z., Clerc-Blankenburg K.P., Davis C., Delgado O., Dinh H.H., Draper H., Gonzalez-Garay M.L., Havlak P., Jackson L.R., Jacob L.S., Kelly S.H., Li L., Li Z., Liu J., Liu W., Lu J., Maheshwari M., Nguyen B.-V., Okwuonu G.O., Pasternak S., Perez L.M., Plopper F.J.H., Santibanez J., Shen H., Tabor P.E., Verduzco D., Waldron L., Wang Q., Williams G.A., Zhang J., Zhou J., Allen C.C., Amin A.G., Anyalebechi V., Bailey M., Barbaria J.A., Bimage K.E., Bryant N.P., Burch P.E., Burkett C.E., Burrell K.L., Calderon E., Cardenas V., Carter K., Casias K., Cavazos I., Cavazos S.R., Ceasar H., Chacko J., Chan S.N., Chavez D., Christopoulos C., Chu J., Cockrell R., Cox C.D., Dang M., Dathorne S.R., David R., Davis C.M., Davy-Carroll L., Deshazo D.R., Donlin J.E., D'Souza L., Eaves K.A., Egan A., Emery-Cohen A.J., Escotto M., Flagg N., Forbes L.D., Gabisi A.M., Garza M., Hamilton C., Henderson N., Hernandez O., Hines S., Hogues M.E., Huang M., Idlebird D.G., Johnson R., Jolivet A., Jones S., Kagan R., King L.M., Leal B., Lebow H., Lee S., LeVan J.M., Lewis L.C., London P., Lorensuhewa L.M., Loulseged H., Lovett D.A., Lucier A., Lucier R.L., Ma J., Madu R.C., Mapua P., Martindale A.D., Martinez E., Massey E., Mawhiney S., Meador M.G., Mendez S., Mercado C., Mercado I.C., Merritt C.E., Miner Z.L., Minja E., Mitchell T., Mohabbat F., Mohabbat K., Montgomery B., Moore N., Morris S., Munidasa M., Ngo R.N., Nguyen N.B., Nickerson E., Nwaokelemeh O.O., Nwokenkwo S., Obregon M., Oguh M., Oragunye N., Oviedo R.J., Parish B.J., Parker D.N., Parrish J., Parks K.L., Paul H.A., Payton B.A., Perez A., Perrin W., Pickens A., Primus E.L., Pu L.-L., Puazo M., Quiles M.M., Quiroz J.B., Rabata D., Reeves K., Ruiz S.J., Shao H., Sisson I., Sonaike T., Sorelle R.P., Sutton A.E., Svatek A.F., Svetz L.A., Tamerisa K.S., Taylor T.R., Teague B., Thomas N., Thorn R.D., Trejos Z.Y., Trevino B.K., Ukegbu O.N., Urban J.B., Vasquez L.I., Vera V.A., Villasana D.M., Wang L., Ward-Moore S., Warren J.T., Wei X., White F., Williamson A.L., Wleczyk R., Wooden H.S., Wooden S.H., Yen J., Yoon L., Yoon V., Zorrilla S.E., Nelson D., Kucherlapati R., Weinstock G., Gibbs R.A.
    Nature 440:346-351(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  7. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  8. "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] (ISOFORM 1).
    Tissue: Mammary gland.
  9. "Mutual interactions between subunits of the human RNase MRP ribonucleoprotein complex."
    Welting T.J., van Venrooij W.J., Pruijn G.J.
    Nucleic Acids Res. 32:2138-2146(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: INTERACTION WITH POP4 AND RPP14.
  10. "Global, in vivo, and site-specific phosphorylation dynamics in signaling networks."
    Olsen J.V., Blagoev B., Gnad F., Macek B., Kumar C., Mortensen P., Mann M.
    Cell 127:635-648(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-154, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  11. "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-154, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  12. Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-154, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  13. "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].
  14. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  15. "System-wide temporal characterization of the proteome and phosphoproteome of human embryonic stem cell differentiation."
    Rigbolt K.T., Prokhorova T.A., Akimov V., Henningsen J., Johansen P.T., Kratchmarova I., Kassem M., Mann M., Olsen J.V., Blagoev B.
    Sci. Signal. 4:RS3-RS3(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-154, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].

Entry informationi

Entry nameiPOP5_HUMAN
AccessioniPrimary (citable) accession number: Q969H6
Secondary accession number(s): A6NL80, Q53FS5, Q9Y2Q6
Entry historyi
Integrated into UniProtKB/Swiss-Prot: May 30, 2006
Last sequence update: December 1, 2001
Last modified: June 24, 2015
This is version 103 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

Miscellaneous

The last C-terminal 19 amino acids are not required for complex association and RNase activity.

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. Human chromosome 12
    Human chromosome 12: 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. 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.